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We've just had a flurry of updates from Starmer and Macron's news conference and have distilled what we now know about the "one in, one out" migrant deal.

Starmer hails the deal as "groundbreaking", saying that migrants arriving via small boats will be "detained and returned to France in short order".

In exchange, he says, others will be allowed to come into the UK via a safe, legal and controlled route. This will be subject to "strict security checks" and will only be open to those who have not previously tried to illegally enter the UK.

The PM explains that the UK offers a "haven" for genuine asylum seekers in dire need, but adds that the country cannot solve the challenge of migration by acting alone.

He confirms the pilot migration scheme will begin "in the coming weeks".

Macron says the deal will open a way for people with family ties in the UK to cross legally but also prevent people being admitted to the UK if they manage the crossing on a one-for-one basis.

He notes that France has strengthened checks and deployed 1,200 security personnel to carry them out. He says that France and the UK are taking steps to improve co-operation with countries of origins to dismantle people smuggling gangs.

Macron says the scheme will be implemented once it has been legally verified and that he hopes this will be as rapid as possible.

The French leader says it is the first time in nine years the UK and France are "providing a response", hailing the exchange deal as an agreement that will get results.

On their nuclear doctrines, Macron says the UK and France have decided to co-ordinate in a way that no two other countries have done so.

This does not take away from the "strategic ambiguity" of it, he adds, making it clear that the two nations will remain "fully sovereign and independent" when it comes to their nuclear capabilities.

Starmer jumps in and calls it "historic", and says they have taken an "incredible step forward" in support of Europe and Nato.

The press conference has now come to an end. Stick with us as we bring you reaction and analysis.

Image source, PA Media

The PM is asked if he can guarantee the plan won't be caught up in the courts. He's also asked how the UK will select those being returned.

Macron is asked how committed he is to making the scheme work, and who is to blame for the number of small boat crossings.

Starmer addresses the final question first, saying France and the UK both have a responsibility to address the problem of illegal immigration and he won't engage in "megaphone politics" and "finger pointing".

In terms of the scheme, he says he won't go into detail - suggesting discussing it could undermine how the scheme operates - but he says it's important to see "this is a breakthrough".

Macron steps in, agreeing France also won't be trading blame and finger-point as he wants to find an efficient way to work together.

He says he's "totally committed" to making the scheme work, reiterating both nations are seeking to establish a working deterrence system. It's in the common interest, he says.

Keir Starmer picks up after Macron finishes, and notes that irregular migration is a worldwide issue, and a common problem for all European countries.

"It requires a serious pragmatic response, not the performative politics of easy answers," he adds.

As a result, Starmer says he and Macron hope to show that social democracy can provide answers to serious problems.

"It is of some significance that while we have been working hard to get a returns agreement, others have been simply taking pictures of the problem," he observes.

Image source, Reuters

Macron is now talking about investing in border protection, saying migrant smugglers are adapting to enforcement.

He adds that the UK and France must now adapt their response.

Macron continues to go after Brexit, saying the British people were "sold a lie" that the problem with migration was Europe.

The French leader says it is the first time in nine years the UK and France are "providing a response", hailing the exchange deal as a good agreement that will get results.

He adds that it will need preventatives measures to stop people wanting to come.

They are now taking questions from journalists. ITV's Robert Peston asks if a pilot scheme that sees relatively few expulsions each week will have any serious deterrent effect?

Starmer responds that it is "ground-breaking" pilot intended to "break the model".

He says if it is successful, they will ramp it up.

For years, the British government has tried to secure a deal like this – and now we've been able to agree on it because we have co-operated and collaborated through "serious diplomacy", he adds.

Image source, Reuters

Macron continues, saying France and the UK are taking steps to improve co-operation with countries of origins to dismantle people's smuggling gangs.

He says the focus remains on addressing the root causes of illegal immigration. Starmer has expressed his full support to efforts to tackle illegal work, he continues.

Macron adds that these are "strong decisions, new decisions" the two leaders have taken to enable safety and security in both countries.

He thanks the British prime minister for hosting the summit and for working to "rebuild" the trust lost following Brexit.

The two leaders shake hands and will now be answering some questions from members of the press.

The French president says that since Brexit, many people in the UK believed the country would be able to better tackle immigration.

But, he says the reality is that the UK has since had no migratory agreement with the EU, meaning there is no legal method for people to cross or to send them back.

Macron suggests this is a pull factor for people to attempt to cross - precisely the opposite of what was promised.

As a result of today's pilot scheme, Macron says the countries will open a way for people with family ties in the UK to cross legally, but also prevent people being admitted if they manage the crossing on a one-for-one basis.

The president says the new scheme will be implemented once it has been legally verified, and he hopes it will be implemented as rapidly as possible.

Macron returns to the issue of small boats, noting the UK and France have previously successfully curbed people entering the UK illegally by rail and road.

He says they have noticed since January an increase in illegal crossings with new "taxi boats", with those using them taking ever-increasing risks.

The French president says he has strengthened checks and today France has 1,200 security forces deployed to do so.

He notes that small boats crossings are a problem on both sides of the Channel.

Macron says the today was about a "reset" on a bilateral level", explaining that trade has topped pre-Brexit levels, which is good for the British economy.

Elaborating on it, he adds that the UK and France have several co-operation agreements, and are strengthening their partnerships in civilian nuclear power - EDF in Sizewell C. He says they are also co-operating in space.

He also mentions the loan of Bayeux Tapestry, and gives Larry the Cat a shout-out too. (In case you missed it, Larry the Cat posted on X about his overwhelming urge to scratch said iconic item.)

Macron now says he's agreed with Starmer to "speed up and accelerate" co-operation on anti-ship missiles in what he described as a "full sweep" to help confront major challenges.

Discussing the meeting of the coalition of the willing earlier, he reiterates there's a "determination" to support Ukraine and describes the virtual summit as a "show of unity".

The French president says the commitment of the 30 countries that have mobilised in support of Kyiv has allowed them to rally US senators now gearing up to launch further sanctions against Russia.

President Emmanuel Macron opens his remarks with thanks to the King for inviting him on a state visit and the "outstanding welcome" offered to his family.

He says the visit, the first by a French president in 17 years, recalls the strength of the Anglo-French alliance and a reset around "shared interests".

Macron highlights the importance of defence and security co-operation, noting that times have changed in Europe and the UK-France partnership "must change accordingly".

He adds that both nations must confront a major conflict in Europe, referencing Russia's full-scale invasion of Ukraine.

Macron says Europe must be able to rely on the strategic collaboration between the UK and France, which is why they signed the Northwood Declaration to co-ordinate the deterrence offered by the nuclear weapons both nations possess.

Image source, PA Media

Referring to the summit on Ukraine the pair co-chaired - with countries of the so-called coalition of the willing - Starmer says as leaders in Nato we play a vital role in preserving peace.

Starmer says they have signed the Northwood Declaration, which would allow the UK and France to co-ordinate their nuclear deterrents for the first time.

Our adversaries will now know that any attack will result in "response from our two nations", the PM adds.

Starmer moves on to discussing further talks on jobs and growth he's had with Macron, saying the two countries "have gone further today" to improve trade and investment.

The prime minister says the UK and France will be strengthening collaboration on supercomputers, satellite connectivity and also work on seizing the opportunities offered by artificial intelligence.

He says he and Macron have agreed to stand together in support of European security and for Ukraine.

Starmer says that he knows some will still question why the UK should take anyone in.

But he explains that the country accepts genuine asylum seekers to provide a "haven" to those in dire need.

But, the PM says that the UK cannot solve a challenge by acting alone, and goes on to praise some of the French government's steps to tackling small boats.

Starmer says he is pleased to announce an agreement on a "ground-breaking" returns scheme.

He says migrants arriving via small boat will be "detained and returned to France in short order".

The PM says in exchange a different person will be allowed to come to the UK by a controlled, safe and legal route.

He adds that this will be subject to "strict security checks" and only open to people who have not tried to enter the country illegally.

Starmer says this will show others trying to make the same journey their efforts will be "in vain". He confirms this pilot scheme will begin "in the coming weeks".

Starmer says today, the task is to look forward in what he calls a "step change in partnership".

He says first on their agenda is illegal migration which is a global and European crisis and that they face a sprawling enterprise run by criminal gangs, which they are determined to end.

Keir Starmer starts off by thanking "firm ally" Emmanuel Macron, saying they have a "shared sense" of the dangerous times we're living through.

"We also share the fundamental belief that we serve our people better, create better jobs and opportunities... if we work together," he says.

UK Prime Minister Keir Starmer and French President Emmanuel Macron have just started a joint news conference.

They're expected to unveil details of a plan to tackle small boat crossings.

You can watch live at the top of our page and we'll bring you the key lines here, so stay with us.