NICOLA Sturgeon has warned the world is facing its "most critical moment" since the Second World War as she urged Boris Johnson to match his "rhetoric with action" on Russian sanctions.

The First Minister said it is a time for leaders to stand up for "independence, for sovereignty, for territorial integrity and for democracy around the world".

She added: "This is probably the most critical moment for the world since the Second World War and time will tell whether the world stands up and defends the values and the principles that we hold dear, or allow people like Putin to ride roughshod over that."

The First Minister also said there would be a "hard lesson" for smaller countries if President Putin is allowed to "get away" with aggression against Ukraine.

"If somebody like Putin can get away with that kind of aggression towards an independent country, then for countries across the world - particularly smaller countries - there is a very hard lesson in that," she said in an interview that was broadcast on the Scottish Goverment's website.

She added the international community must be "vigilant" against Russian retaliation to sanctions through cyber attacks.

"I think that is something that we have to be very vigilant about," she said.

"The discussions I've mentioned already about domestic impacts, cyber security is one of those.

"We know, even before the current situation in Ukraine, that Russia was very active around cyber activity."

The First Minister said on Tuesday she did not believe the first tranche of sanctions went far enough and told STV News on Wednesday more had to be done after aggression in Ukraine.

"I don't think that the UK Government is yet doing enough in the form of sanctions," she said.

"We've had, rightly and properly, some very tough rhetoric from Boris Johnson and the UK Government in recent weeks, we now need that rhetoric matched by action.

"That's important because this is a critical moment for Ukraine, but it's a critical moment for the world.

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"The choice at this moment in history is to hit Putin hard with the severest of sanctions so that he understands there will be consequences for his imperialist aggression, or we don't do that and he becomes further emboldened.

"It's really important that the international community stands together, stands in solidarity with Ukraine as it defends its independence and sovereignty, but also stands together to act in a way that shows Putin and dictators like him that there are serious consequences for this type of action."

The First Minister was speaking after a meeting with the Ukrainian Consul General and the chairwoman of the Association of Ukrainians in Great Britain in Edinburgh. 

Ms Sturgeon went on: "London is awash with Russian money and the UK Government must target that wealth, those assets, wherever they are and the Russian interests that benefit from those assets and wealth.

"They will know where those assets are but there must be a very serious, systematic approach to sanctions and there must be efforts made to ensure that trade is disrupted to make sure that Russia feels that."

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She said it should be the "elite" of Russia that should be impacted by any sanctions and not the citizens, adding that the Scottish Government would support any action against Russian interests in Scotland.

The First Minister went on to urge the international community not to "move on" from what is happening in Ukraine.

"This is a moment where Putin has to be left in no doubt," she said.

"Because what we have seen in the past with Crimea, with Georgia before it, is that the world is aghast for a short time and then it moves on, and Putin is left to consolidate his gains and think that he can continue to act in this way with no consequence whatsoever."

Meanwhile, at Prime Minister's Questions on Wednesday in the Commons, SNP Westminster leader Ian Blackford asked Johnson why  "under the Tories a sewer of dirty Russian money has been allowed to run through London for years".

He said: "I went to the Prime Minister, the then foreign secretary in 2017, and I raised the issue of limited partnerships, 113 of which have been used to move 20.8 billion dollars out of Russian banks.

"Corruption on an industrial scale. Why did the Prime Minister do nothing back then and why is he still doing nothing now?"

The Prime Minister said he was grateful for the question being raised and Mr Blackford was "right" to raise the issue back then and "right on the issue", adding: "We do need to stop corrupt Russian money in London and every other financial capital.

"That's why we have already taken the steps that we have taken but we are going much further to uncloak the true owners of Russia companies and Russian properties in this country. And high time. No country is doing more than the UK to tackle this issue."

Blackford then pressed Johnson on donations made by Russian oligarchs to the Conservative party.

"The truth is that Russian oligarchs who give the right people in power a golden handshake have been welcomed into London for years," Blackford said.

"Their activities were not stopped; they were encouraged. Plenty of those golden handshakes just so happened to find their way into the coffers of the Conservative party—in fact, £2.3 million since the Prime Minister took office.

"A leading American think-tank has publicly raised concerns that 'the close ties between Russian money and the United Kingdom’s ruling Conservative Party' are a block to stronger sanctions.

"How can our allies trust this Prime Minister to clean up dirty Russian money in the UK when he will not even clean up his own political party? Will he finally commit to giving up the £2.3 million that his party has raised from Russian oligarchs?"

The Prime Minister responded: "I just think it is very important for the House to understand that we do not raise money from Russian oligarchs...We raise money from people who are registered to vote on the UK register of interests. That is how we do it."