During a conference in the Ukrainian capital of Kiev, British Prime Minister Boris Johnson stated that Russian military crowds on Ukraine's border show what he called "Moscow's hostility."

Any Russian invasion of Ukraine would be a disaster, Johnson said, warning the latter would backfire on Moscow, which says the West does not respect its security demands.

The British Prime Minister expressed the hope that Russia would engage in the delusional path of seeking a solution to the current crisis.

Johnson's visit to Ukraine, in the framework of Western support for Kiev, comes amid fears that Russia will be "invading" at an imminent time.

For his part, the Ukrainian President, Vlodemir Zelensky, praised the Allied support, saying that Britain had provided military assistance to Kiev.

Referring to Ukraine's crisis, exacerbated by Moscow's refusal to join NATO in Kiev, Russian President Vladimir Putin said it was wrong to strengthen one state's security at the expense of another.

Putin stated at a press conference in Moscow that his country was seeking long-term security assurances, adding that Russia had not received the required response from the West on two outstanding security points.

Moscow has confirmed that it will not back down in the face of threats of US sanctions, and the Russian Embassy in Washington said on its Facebook account that "it is Washington that is fuelling tensions, not Moscow."

"We will not back down and listen carefully to threats of American sanctions," the Russian Embassy added, according to France Press.

Washington and the West threaten to impose sanctions on Russia if it invades Ukraine. President Biden said he was willing to impose sanctions on his Russian counterpart Vladimir Putin personally. Washington and Berlin also hinted at the disruption of the Baltic Sea pipeline Nord Stream 2.

In the meantime, the European side is not hiding concerns about the repercussions of any possible sanctions on gas supplies from Russia, given that Moscow secures up to 40 percent of the gas to the Old Continent.

Since the end of last year, Kiev and its Western allies have accused Russia of mobilizing up to 100,000 troops on its western border (with Ukraine) in preparation for its invasion.

On Monday, White House spokeswoman Jane Saki said her country had prepared "sanctions targeting members of the Russian elite and their families," should Russia invade Ukraine.