Kyiv estimates that 5% of the world's "critical raw materials" are in Ukraine - including:

• 19 million tonnes of proven reserves of graphite, which is used to make batteries in electric vehicles
• A third of all European lithium deposits, the key component in current batteries
• Significant deposits of rare earth metals, used to produce weapons, wind turbines, electronics and other products vital in the modern world

Before Russia's invasion three years ago, Ukraine also produced 7% of the world's titanium, used to make everything from power stations to planes. According to Ukraine's Economy Minister, Yulia Svyrydenko, resources worth $350bn have been seized by Russia since its invasion three years ago.

US aid in Trump era comes with strings attachedpublished at 06:38 Greenwich Mean Time 26 February

06:38 GMT 26 February

Anthony Zurcher
North America correspondent

"That’s what I do. I do deals," Donald Trump said at his news conference with French President Emanuel Macron on Monday. "My whole life is deals."

Now, Ukrainian officials have told the BBC the American president has his rare-earth deal with Ukraine, and Trump has suggested Zelensky will visit Washington DC on Friday to sign the deal.

According to the Ukrainian sources, the US had to back away from some of its more onerous demands from the war-torn nation. And many of the details of this agreement will require further negotiation.

The precedent, however, is set. US aid in the Trump era comes with strings attached. Aid for aid's sake – whether given for humanitarian or strategic reasons – is a thing of the past.

That represents a fundamental reordering of American foreign policy for more than 75 years, from the days of the Marshall Plan to post-Cold War idealism and George W Bush’s "Freedom Agenda" push to promote global democracy.

Ukraine is just the start. Expect Trump and his foreign policy team to apply their "America First" principles around the world over the course of the next four years.

Without confirming an agreement had been reached, Trump says he expects Zelensky to sign a minerals deal during a visit to Washington this week, saying that in return, Ukraine would get the "right to fight on".

"Without the United States and its money and its military equipment, this war would have been over in a very short period of time", Trump said on Tuesday, adding that there would be a need for "some form of peacekeeping" in Ukraine following a peace deal.

Trump said he has been pushing for access to Ukraine's mineral deposits in return for the military aid the US has given to the country.

"We want to get that money back," he said.

Image source, Getty Images

As we've been reporting, a senior official in Kyiv has told the BBC that Ukraine has agreed the terms of a major minerals deal with the US.

We don't have much detail on that deal yet, but here's what we do know:

• Media reports say Washington has dropped initial demands for a right to $500bn (£395bn) in potential revenue from accessing Ukraine's natural resources
• The same reports suggest the US has not given firm security guarantees to Ukraine - which has been their key demand
• Donald Trump said on Tuesday that in return for the deal Ukraine would get "the right to fight on", but didn't confirm if the US would continue supplying military equipment and ammunition
• The US president said he's expecting Ukrainian President Volodymyr Zelensky in Washington to sign the deal this week
• Ukraine's Deputy Prime Minister Olha Stefanishyna, who has led the negotiations, told the Financial Times that the deal is "only part of the picture"
• As a reminder, Ukraine holds huge deposits of critical elements and minerals, including lithium and titanium, as well as sizeable coal, gas, oil and uranium deposits - supplies worth billions of dollars

Nathan Williams
Live page editor

Hello and welcome as we continue our live coverage of the events around the war in Ukraine.

Donald Trump says that he's expecting his Ukrainian counterpart Volodymyr Zelensky to a sign a "very big" minerals deal with the US this week.

A senior official in Kyiv has told the BBC that Ukraine has agreed the terms of the deal which will allow the US to jointly exploit its mineral resources - a key demand of Trump who wants Kyiv to repay US military aid.

The deal was apparently agreed after Trump's original demand for $500bn (£395bn) in potential revenue was dropped – but it does not include firm security guarantees to war-torn Ukraine.

Without confirming that an agreement had been reached, Trump said on Tuesday that in return for the deal Ukraine would get "the right to fight on".

Stay with us as we continue to follow events and take your through all the reaction.