Anastassia Levchenko
Reporting from Kyiv

Another Ukrainian politician has given their take on Putin's warning that Nato would be "at war" with Russia if it allowed Ukraine to use long-range missiles.

Oleksiy Honcharenko, of the European Solidarity party, tells the BBC that Western leaders must use "the language of strength" - which is all that Vladimir Putin understands.

He describes last night's statement as "blackmail", adding that "we've seen it many times, it's an old KGB trick".

For context: The KGB was the security service of the former Soviet Union, which Putin worked for. The FSB, who expelled the six British diplomats, is widely regarded as one of its successor organisations. Putin is also the former head of the FSB.

Honcharenko tells me: "But [Putin] sees that, unfortunately, Western countries are really are not strong in their position, and they're wavering about the decision to give to Ukraine the possibility to attack military targets in Russian territory.

"He feels this weakness as a predator. So he tries to push here, and he tries to threaten the free world."

Central to the fallout this morning is Russia's war in Ukraine, which has been raging for two-and-a-half years now. Here's what has been happening on the frontlines recently:

• Ukraine sent units into Russia in early August, advancing up to 18 miles (30km) into the region of Kursk, prompting evacuations of civilians from areas along the border
• After two weeks, Ukraine's top commander claimed to control more than 1,200 sq km of Russian territory and 93 villages, though in recent days, Russia has claimed to have regained some
• Russia's main offensive continues on the eastern Donetsk region, as it has for a long time now. Its troops recently made some significant gains to the north-west
• In response, Ukraine ordered the evacuation of the city of Pokrovsk, with a local military official telling residents that Russian forces were "rapidly approaching"
• Meanwhile, Russia has also continued to attack other cities elsewhere in Ukraine, such as Kharkiv and the capital Kyiv

If you'd like a more in-depth update on the situation on the ground, the BBC is tracking it here.

The US president could be on the verge of allowing Ukraine to use Western-made long-range missiles deep inside Russia, according to European officials, the New York Times reports.

But there would be a caveat – Ukraine wouldn’t be allowed to use weapons provided by the US for that purpose.

Joe Biden’s discussing the issue with British prime minister Keir Starmer in Washington today.

It would be part of a coordinated strategy, to help Ukraine push back after Russia’s full-scale invasion in February 2022.

The Anglo-French cruise missile Storm Shadow, which has a maximum range of around 250km (155 miles) is considered an ideal weapon for penetrating bunkers and ammunition stores.

The UK and France have already sent the weapons to Ukraine, but the caveat until now has been that it could only be used within Ukraine’s own borders.

Kremlin spokesman Dmitry Peskov says Russian President Vladimir Putin's latest warning against the West is "extremely unambiguous".

Putin issued a warning that the UK and US could allow Ukraine to use Western-supplied long-range weaponry against targets deep inside Russia.

"The statement Putin made yesterday is a very important one. It is extremely clear, unambiguous. It does not lend itself to multiple interpretations.

"We are in no doubt that this statement has reached its addressees," Peskov says, as quoted by Interfax news agency.

• Russia's FSB security service has revoked the accreditation of six British diplomats, claiming they are suspected of spying and "threatening Russia's security"
• In a statement, the FSB added that the move was in response to "numerous unfriendly steps" by London

• A spokesperson for Russia's foreign ministry accused the British embassy of going far beyond diplomatic convention
• The UK Foreign Office says the accusations against its staff are "completely baseless"

• It comes as Prime Minister Keir Starmer is in Washington for talks with US President Joe Biden
• Allies of Kyiv are discussing whether to give Ukraine permission to fire missiles they have provided towards targets inside Russia

• Russian President Vladimir Putin has suggested Moscow would regard Western missiles being fired into Russia as a serious escalation of the war

Anastassia Levchenko
Reporting from Kyiv

Vladimir Putin's comments on the West allowing Kyiv's use of longer-range missiles being a declaration of war are an "illusion" and part of Moscow's regular playbook, a Ukrainian MP tells the BBC.

"We have seen from Putin over the last two-and-a-half years.

"They keep identifying certain things as the red lines and hoping that it will influence Western politicians and create a delay in providing Ukraine with much-needed solutions," says Kira Rudik, Voice Party leader and vice-president of Alliance of Liberals and Democrats for Europe Party.

"It has been the same way with the tanks, with the long-range missiles, with the fighter jets. And what we have seen is that it was an illusion, because Russia keeps destroying our country, keeps killing our people, and they are not changing their strategy, no matter what the West do."

She says Ukraine's allies should "ignore Putin's threats" and "arm us with everything needed as soon as possible".

"Every day of the delay means that more people will die in Ukraine, and we need to stop that," she adds.

The UK's Foreign Office has just released a statement calling the accusations made by Russia's FSB security service against its staff as "completely baseless".

“The Russian authorities revoked the diplomatic accreditation of 6 UK diplomats in Russia last month, following action taken by the UK government in response to Russian state directed activity across Europe and in the UK," the statement says.

“We are unapologetic about protecting our national interests.”

Jacqueline Howard
Live reporter

The Kremlin is attempting to present Britain at the front of the "anti-Russia campaign", a Russia specialist says, after Moscow withdrew the accreditation of six British diplomats.

Professor Mark Galeotti, an expert on modern Russia at the Rusi think tank, told me the move reflects that Russia is particularly annoyed with Britain, which, along with the US, is seen as leading military support for Ukraine.

It's bad news, he says, because the British embassy in Moscow is already "pared to the bone", and the UK needs to maintain its diplomatic connections with the country.

Prof Galeotti adds that Vladimir Putin appears more reckless than his Soviet Union predecessors: "They would occasionally expel diplomats believed to be spies or for political reasons, but they understood that it was important to have robust diplomatic connects."

"Putin has gone further and it is alarming," he says.

Putin draws new red line on long-range missilespublished at 10:03 British Summer Time 13 September

10:03 BST 13 September

Steve Rosenberg
Russia editor

From the tone of President Putin’s latest remarks, it’s clear he considers that the targeting of internationally recognised Russian territory with Western missile systems would take the conflict to a new level. What he didn’t make clear is how Moscow would respond.

“We will take corresponding decisions based on the threats to us that will be created,” Putin said.

On Friday, Russia withdrew the accreditation of six British diplomats, accusing them of “subversive activities” and threatening Russia’s security. But Putin’s potential response is much broader.

He offered some clues back in June. At a meeting with the heads of international news agencies, he was asked: how would Russia react if Ukraine was given the opportunity to hit targets on Russian territory with weapons supplied by Europe?

“First, we will, of course, improve our air defence systems. We will be destroying their missiles,” President Putin replied.

“Second, we believe that if someone is thinking it is possible to supply such weapons to a war zone to strike our territory and create problems for us, why can’t we supply our weapons of the same class to those regions around the world where they will target sensitive facilities of the countries that are doing this to Russia?”

In other words, arming Western adversaries to strike Western targets abroad is something that Moscow has been considering.

Read Steve Rosenberg's full analysis

Sending missiles into Russia won't win Ukraine the warpublished at 09:45 British Summer Time 13 September

09:45 BST 13 September

Jeremy Bowen
International editor

Ukraine has said it has a list of targets it would pursue if the West were to allow Ukraine to fire Western missiles into Russia.

What they won't be able to do is head off the current Russian campaign to capture Pokrovsk in the east, which is a very important railway junction.

So, throughout the war, as Ukraine's President Volodymyr Zelensky has pushed for stronger, better weapons, none of them have been a miracle in all of this, they have not given Ukrainians the victory they want, in fact far from it.

If Ukraine were to be permitted to send Western missiles into Russia, this might change some of the details of what is going on and will give Ukrainians, certainly, something else to hit the Russians with, but it won't win the war for Ukraine.

Putin is giving every indication that this is a very important strategic decision for him - that he doesn't want Ukraine to be a bastion of the West, and my view is the war will continue as long as he is in the Kremlin.

Image source, EPA

Poland's Prime Minister Donald Tusk says he's not worried by Putin's comments that Moscow would view Western missiles being fired into Russia as a serious escalation of the war.

"It is necessary to take all events in Ukraine and on the Ukrainian-Russian front very seriously, but I would not attach excessive importance to the latest statements from President Putin," Donald Tusk told a news conference.

"They rather show the difficult situation the Russians have on the front."

The British embassy in Moscow had gone well beyond diplomatic convention, Russia's foreign ministry says.

Spokesperson Maria Zakharova said the ministry agreed with the FSB security service's "evaluation of the activities of these so-called British diplomats".

"The British embassy has largely flouted the limits set by the Vienna Convention," she says, before going on to accuse the embassy of "actions aimed at causing harm to our people".

Putin's war warning isn't a dramatic change in rhetoricpublished at 08:42 British Summer Time 13 September

08:42 BST 13 September

Vitaliy Shevchenko
Russia editor, BBC Monitoring

Putin’s threat to respond should Nato become “directly involved” in the Ukraine conflict by allowing Kyiv to strike Russian territory with Western-made long-range missiles marks an escalation, but not a dramatic change in rhetoric.

Kremlin-controlled media have long been saying that Western countries are already heavily involved in the war by providing weaponry, training, etc, and some Russian sources have even claimed that Western boots were already on the ground in Ukraine.

The point Russian media have been making repeatedly is that otherwise Russia would have crushed Ukraine a long time ago were it not battling “the whole of Nato”.

Also, Moscow has repeatedly said that it is prepared to use all available means to defend itself – including nuclear weapons “in case its sovereignty and territorial integrity are threatened“.

This is contained in its nuclear doctrine, and there have been suggestions coming out of Moscow recently that it may be changed, possibly to make the deployment of nuclear weapons easier.

This is how deterrence works – don't help Ukraine or else.

We're hearing reaction now from Lord Peter Ricketts, a former national security adviser, who says Russia's reported move to revoke the accreditation of six British diplomats in Moscow is "Russian punishment for the UK being seen as a cheerleader for supplying weapons to Ukraine".

He tells BBC Radio 4's Today programme that the reasons Russia's security service gave in its statement are "completely trumped up'.

"We're told the Russian spy agency has documents from a department in the foreign office, which say that the task of the embassy is ensuring Russia's strategic defeat against Ukraine.

"Well, surprise, surprise", says Lord Rickets.

"That has been British declared politics for two-and-a-half years."

The embassy is not a large one, Lord Ricketts adds, so this will, for a time, "diminish what the embassy can do".

PM defiant in response to Putin war threatpublished at 08:10 British Summer Time 13 September

08:10 BST 13 September

Chris Mason
Political editor, reporting from Washington

There was a clear defiance from the prime minister in response to President Putin's threat of escalation. Starmer repeatedly told us “Russia started this", Moscow caused the conflict and it could stop it.

The prime minister and other western leaders are guarded in their public remarks about a change in policy on the use of missiles but the diplomatic dashing to arrive at a decision is in plain sight.

Foreign Secretary David Lammy and the US Secretary of State Antony Blinken were in Kyiv this week.

On Sunday, Starmer will head to Rome - Italy currently holds the rotating presidency of the G7 group of industrialised countries. World leaders will gather at the UN General Assembly in New York a week later.

“There are really important developments likely in the next few weeks and months and therefore a number of tactical decisions ought to be taken,” Starmer says.

Image source, Reuters

Russia started the conflict in Ukraine and can end it "straight away”, Prime Minister Keir Starmer said.

His comments come after Russian President Vladimir Putin warned Russia would be at war with Nato if it allowed Ukraine to use long-range weapons to target Russia.

Starmer, who is in Washington for talks with US President Joe Biden, said: “Russia started this conflict. Russia illegally invaded Ukraine. Russia can end this conflict straight away."

He later added: “To reiterate, it was Russia who started this in the first place. They caused the conflict, they’re the ones who are acting unlawfully.”

Read more: Russia can end war now, says PM as Putin warns West

Is Putin's threat of escalation a bluff?published at 07:30 British Summer Time 13 September

07:30 BST 13 September

Frank Gardner
Security correspondent

Is Vladimir Putin bluffing? That’s the calculation that strategic planners – and elected leaders – in Washington and other western capitals now have to make.

Those in favour of allowing Ukraine to fire long-range missiles into Russia argue that so far in this war, none of his so-called ‘red lines’ have amounted to anything.

The Russian leader hinted at retaliation if the West supplied Ukraine with main battle tanks, with long-range artillery and then with F16 warplanes. Each time nothing happened.

Putin already believes his country to be at war with Nato in all but name, so, some argue, what difference would this make? But if Russia did retaliate this time then it has a broad spectrum of options short of declaring war.

At the milder end of the spectrum, it could launch so-called ‘sub-threshold’ attacks, such as cyber attacks, interfering with undersea cables or sending drones to disrupt Western air traffic.

Other, far more dangerous but less likely options would include detonating a tactical nuclear warhead against Ukraine or attacking a weapons supply base inside a Nato country like Poland. And those scenarios are exactly what Washington is desperate to avoid.

• Moscow has revoked the accreditation of six British diplomats, according to Russian media
• The Russian FSB security service says are suspected of espionage and "threatening Russia's security"
• It says that the move was a measure against "multiple unfriendly acts"
• Meanwhile, Russian President Vladimir Putin suggested Moscow would regard Western missiles being fired into Russia as a serious escalation of the war
• It would “mean nothing other than the direct participation of Nato countries - the US and European countries - in the war in Ukraine", Putin told state television

• UK Prime Minister Sir Keir Starmer brushed aside the warning, saying Ukraine had the right to defend itself, but he added that he did not seek conflict with Moscow
• Starmer is in Washington for talks with US President Joe Biden, as allies of Kyiv discuss giving Ukraine permission to fire their missiles at targets inside Russia

Stay with us for more.

Russian President Vladimir Putin has warned Nato was at risk of entering into war with Russia if Europe and the US allowed Kyiv to attack Russian territory with western-made long-range western missiles.

Putin told Russian state television that this would “mean nothing other than the direct participation of Nato countries - the US and European countries - in the war in Ukraine."

"It is their direct participation," he said. "And, of course, this substantially changes the very essence, the nature of the conflict.”

He added: “If that is the case, we will take corresponding decisions based on the threats that will be created to us.”

Welcome to our coverage. You're joining us as Russia media report that Moscow has revoked the accreditation of six British diplomats it accuses of spying.

The FSB state security service claimed their activities threatened the country's security.

It comes as Russian President Vladimir Putin warns the West it was at risk of entering into war with Russia. Putin said Moscow would take “appropriate decisions” if Nato allowed Ukraine to strike Russian territory with Western-made long-range missiles.

Stay with us for live updates and analysis.