Reports of a planned "humanitarian intervention" in Ukraine by Russian armed forces have been met with "grave concern" by the Prime Minister and US President, Downing Street says.
Any such move would be "unjustified and illegal" and would prompt "further and tougher sanctions", the two leaders were said to have agreed in a telephone call.
"They reiterated that we continue to urge Russia to engage with the international community and the Ukrainian government to find a political solution to the crisis," a Number 10 readout of this afternoon's call said.
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Theresa May will set out the plans in a speech in Cheshire on science.
The Foreign Secretary said Theresa May needs ‘time and space’ to reach a deal.
A good deal of dry and sunny weather as we head towards the next Bank Holiday weekend