Boris Johnson ha said Vladimir Putin has “chosen a path of bloodshed and destruction”, and is expected to announce further sanctions against Russia.
The Prime Minister is leading a crisis meeting of senior ministers and officials to consider how to respond to Vladimir Putin’s military action against Ukraine.
Why has Russia invaded Ukraine
Mr Putin announced military action during a televised address early on Thursday morning, saying the move was a response to threats from Ukraine.
He said Russia does not have a goal to occupy Ukraine, but the responsibility for bloodshed lies with the Ukrainian “regime”.
He also warned other countries that any attempt to interfere with the Russian action would lead to “consequences they have never seen”.
Mr Putin accused the US and its allies of ignoring Russia’s demand to prevent Ukraine from joining Nato and offer Moscow security guarantees.
He said the Russian military operation aims to ensure a “demilitarisation” of Ukraine, adding that all Ukrainian servicemen who lay down arms will be able to safely leave the zone of combat.
Explosions could be heard in the Ukrainian capital of Kyiv shortly after Mr Putin’s address, while explosions were also reported in the cities of Odesa and Kharkiv.
Ukraine’s border guard agency said the Russian military attacked the country from neighbouring Belarus.
The agency said that the Russian troops unleashed an artillery barrage as part of an attack backed by Belarus.
Ukraine live stream as Russia begins military operation
Ukraine civilians are attempting to leave the capital of Kyiv ad Russian forces begin military invasion.
A live stream shows Maidan Square in Ukraine following a night of military attacks.
The Prime Minister – whose initial package of sanctions was criticised by senior Tories and opposition figures – has promised to respond “decisively” to the Russian onslaught.
“I am appalled by the horrific events in Ukraine and I have spoken to President Zelensky to discuss next steps,” he said.
“President Putin has chosen a path of bloodshed and destruction by launching this unprovoked attack on Ukraine.
“The UK and our allies will respond decisively.”
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