A serious gas leak has closed Whitehall in London, prompting police to change plans for protesters demonstrating against the invasion of Ukraine.
Thousands of people had been expected to turn out in the area today in support of the under siege nation.
Instead, the Met Police is in the middle of making "alternative arrangements" amid safety fears over the gas leak.
The force wrote on Twitter: "Whitehall has been closed due to a serious gas leak, and is likely to remain closed for some time.
"We are in the process of making alternative arrangements for planned protests in the area today.
"If you are attending, please follow the instructions of police officers. Thank you."
The news followed two solid days of protests outside Downing Street, with thousands calling on the government to "step up" and do more to support the Ukrainian people under attack from their Russian neighbours.
A 4,000 strong crowd first gathered in Whitehall on Friday evening as teary-eyed protesters demanded action after a sea of sanctions were put forward by the Prime Minister.
Among them was Maryna Nekliudova, 34, with her husband who has a close friend in Kyiv staying in a makeshift bomb shelter in their apartment building with her three-year-old twins.
She said: “I’m completely devastated. They couldn’t even leave the city.
"Every time they tried to leave with their cases the air raid siren would go off.
“Those kids should not know war. We have not done anything. We are a peaceful nation and this is completely unprovoked.”
Thousands more were back on Saturday to continue the protest and had been planning to return today before this morning's news.
Several people on social media refused to believe there was a leak, with some describing it as "convenient".
One wrote: "At any other time, I would take this at face value. Right now? I smell something rotten and it ain't gas."
Another added: "That's a tad convenient."
It comes as the Prime Minister praised Ukrainians for "fighting heroically" as allies unveiled new measures to hit Russia's financial system and Liz Truss said the Foreign Office is preparing a "hit list" of oligarchs to sanction.
After talking by telephone to Ukrainian President Volodymyr Zelensky, Mr Johnson said the West had to do everything possible to change the "very heavy odds" against Ukraine in its struggle against Moscow's forces.
Confirming Britain would be sending further arms to the Ukrainians, he said that the financial measures were essential to put pressure on the Kremlin.
He said: "It is incredibly important for tightening the economic ligature around the Putin regime.
"Let's be in no doubt, things are not going all the way of President Putin, very far from it.
"The Ukrainians are fighting heroically, and in some places with great success, as many of us thought they would because they're a great country and a very brave country."
