Watch live footage from Maidan square in Kyiv, Ukraine

A Cabinet minister has warned that an imminent incursion by Russian troops into Ukrainian territory was “entirely possible”, and that it was clear Vladimir Putin’s build-up of troops on the border made it possible for Russia to move “very, very swiftly”.

With 130,000 Russian troops massed along Ukraine’s border, the US has also claimed war could begin at any moment and, along with several other countries, has advised its citizens to leave the country immediately.

On Saturday, Joe Biden and Mr Putin spoke for an hour on the phone.

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