U.S. President Joe Biden attends an event on fighting "ghost guns" crimes at the White House in Washington, D.C., the United States, April 11, 2022. (Xinhua/Liu Jie)

President Joe Biden also proposed legislation to hold Russian oligarchs accountable for their alleged role in supporting the military operation.

U.S. President Joe Biden on Thursday requested that Congress appropriate 33 billion U.S. dollars to help Ukraine defend itself from the ongoing military operation by Russia.

Delivering remarks from the White House, Biden elaborated on how the newly proposed supplemental funding will be used. Of the 33-billion-dollar sum, according to a fact sheet by the White House, 20.4 billion dollars will be military and security assistance to Kiev, 8.5 billion dollars will be spent in economic assistance for the Ukrainian government and people, and 3 billion dollars will be allocated for additional humanitarian assistance and food security funding, and targeted funding to address economic disruptions caused by the war.

"It's critical this funding gets approved and approved as quickly as possible," the president said.

Biden also proposed legislation to hold Russian oligarchs accountable for their alleged role in supporting the military operation. One of the aims of the proposed legislation is to improve the United States' ability to use forfeited oligarch funds to remediate harms caused to Ukraine by Russia's military operation, said a separate fact sheet by the White House detailing the proposal.

In an effort to assuage speculations over the possible use of nuclear weapons as the hostility between Russia and Western powers shows no sign of abating, Biden said "no one should be making idle comments about the use of nuclear weapons or the possibility of the need to use them."

He criticized Russian Foreign Minister Sergei Lavrov for making "irresponsible" remarks earlier this week on the prospect of a nuclear conflict.

Lavrov told Russian media in an interview broadcast on Russian TV on Monday that preventing nuclear war is Moscow's "key position on which we base everything. The risks now are considerable." He added: "I would not want to elevate those risks artificially. Many would like that. The danger is serious, real. And we must not underestimate it."