President Joe Biden of the United States issued a strong warning to Russian President Vladimir Putin on Thursday.

If Putin deployed a chemical weapon in his attack on Ukraine, Biden said, NATO would "react."

"If he uses it, we'll reply." After a NATO conference in Brussels, Biden said, "The nature of the response would depend on the nature of the usage."

He claimed that the Western alliance was listening to everything coming out of Ukraine and would respond appropriately if Russia went over its limits.

Biden declared that "NATO has never been more united" in its fight against Russia, and announced that his administration has offered $2 billion in arms to Ukraine.

The US president also promised to admit 100,000 of the approximately 3.7 million refugees fleeing the country, as part of a fresh commitment of "more than $1 billion in humanitarian assistance."

He claimed that the West was in it for the long term, with the goal of "raising the agony" on Moscow while stepping up efforts to exclude Russia from the G20 and replace it with Ukraine.

According to CNN, Biden told reporters, "That was raised today."