Britain on Tuesday sanctioned five Russian banks and three individuals in response to Russia’s recognition of Ukraine’s separatist regions.
The Russian banks sanctioned are Rossiayaz Bank, IS Bank, General Bank, Promsvyazbank and the Black Sea Bank, Prime Minister Boris Johnson has announced.
Gennady Timchenko, Igor Rotenberg and Boris Rotenberg are the individuals targeted by the sanctions and their assets in the UK will be frozen, Johnson said.
He said this was only the “first tranche” of measures and even more sanctions would be announced in case Russia prefers to go for a full-scale invasion of Ukraine.
"We should steel ourselves for a protracted crisis," the prime minister said.
Johnson said “we must brace ourselves" for the next move by Russia after it "flagrantly violated" the Minsk agreements last night.
"In a single inflammatory speech, he (Russian president) denied that Ukraine had any ‘tradition of genuine statehood’, claimed that it posed a ‘direct threat to the security of Russia’, and hurled numerous other false accusations and aspersions," he said.
The prime minister said: "Soon afterwards, the Kremlin announced that Russian troops would enter the breakaway regions under the guise of ‘peacekeepers’, and Russian tanks and armored personnel carriers have since been spotted.
"The House should be in no doubt that the deployment of these forces in sovereign Ukrainian territory amounts to a renewed invasion of that country.
"And by denying Ukraine’s legitimacy as a state – and presenting its very existence as a mortal threat to Russia – (Vladimir) Putin is establishing the pretext for a full-scale offensive."
He said: "If the worst happens then a European nation of 44 million men, women and children would become the target of a full-scale war of aggression waged without a shred of justification for the absurd and even mystical reasons that Putin described last night."
Johnson told the lawmakers that he has "spoken on a number of occasions to President Putin since this crisis began and so has President (Joe) Biden, while President (Emmanuel) Macron and Chancellor (Olaf) Scholz have both visited Moscow."
"Together we have explored every avenue and given Putin every opportunity to pursue his aims by negotiation and diplomacy."
Johnson said that "we will not give up: we will continue to seek a diplomatic solution until the last possible second, but we have to face the possibility that none of our messages has been heeded and Putin is implacably determined to go further in subjugating and tormenting Ukraine."
"And it is because we suspected as much that the UK and our allies repeatedly sounded the alarm about a possible new invasion, and we disclosed much of what we knew about Russia’s military build-up," he added.