A minute's silence will be held today (Feb 24) at 11am, to mark a year since the war in Ukraine started - it comes as four protestors are arrested in London.
They had painted a huge Ukraine flag on the road outside the Russian embassy in London, to mark the date.
The Led By Donkeys campaign group took responsibility for the 500 square metre blue and yellow flag which covered Bayswater Road on Thursday morning.
The protesters intended to send a direct message to Russian leader Vladimir Putin with the stunt, they added.
Led by Donkeys said:
"Tomorrow is the first anniversary of Putin's imperialist invasion of Ukraine.
"Contrary to what the Russian dictator and his apologists claim, Ukraine is an independent state and a people with every right to self-determination.
"The existence of a massive Ukrainian flag outside his embassy in London will serve to remind him of that."
Three males and one female were arrested "on suspicion of criminal damage and obstructing the highway", the Metropolitan Police tweeted.
"They remain in custody."
Traffic was temporarily obstructed as the campaigners pushed wheelbarrows laden with paint, then smothered it onto the road.
One of the protesters held a sign saying: "Ukrainian Solidarity Protest - Drive slowly - Washable paint."
The activists added the paint used to create the flag was "high-standard, non-toxic, solvent-free, eco-friendly, fast-dry edible paint designed for making road art".
Led By Donkeys has made a name for itself with political stunts, such as giant billboards holding politicians to account for their tweets.
Another recent high profile stunt by the group came in October last year, after the disastrous economic policies of the short-lived Liz Truss government.
Led By Donkeys placed a plaque reading "The UK economy was crashed here" outside 55 Tufton Street, targeting conservative think-tanks said to have influenced the then-prime minister's approach.
The protest came after Vladimir Putin spoke at a pro-war rally before the first anniversary of Russia's invasion of Ukraine, where he called on spectators to chant "Russia, Russia" in a show of support for those serving in the armed forces.
Meanwhile, the Ukrainian foreign minister insisted his country would not use Western fighter jets to strike targets in Russia.
(c) Sky News 2023: Ukraine flag stunt outside Russian embassy in London on eve of invasion anniversary
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