Updated March 24, 2022 2:54 PM ET

President Biden promised allies would react if Russia used chemical weapons against Ukraine.

“That would trigger an in-kind response,” Biden told reporters. “Whether or not you ask if NATO would cross, we would make that decision then.”

Biden is in Brussels to meet with NATO allies for emergency talks as Russia’s invasion of Ukraine enters its fourth week.

At a news conference at NATO headquarters on Thursday, Biden said more weapons were flowing in to help Ukraine as Western leaders meet to discuss contingency plans in case Russian aggression would intensify.

Biden said Russian President Vladimir Putin misjudged the unity of the West.

“NATO has never, ever been as united as it is today,” Biden said. “Putin is getting the exact opposite of what he intended by going to Ukraine.”

Biden added that he thinks Russia should be kicked out of the G-20, but noted that the decision would be up to the group. If the members object, he thinks that Ukraine should be able to attend the next meeting.

Russia was part of the G-8 group of major economies until it was expelled for annexing Crimea in 2014.

“Putin is getting the exact opposite of what he intended by going to Ukraine,” Biden said.

Biden bristled at suggestions sanctions didn’t deter Putin from invading Ukraine

“Sanctions never deter,” he said, adding that keeping the sanctions in place for months to come is “what will stop it.”

Biden’s mission ahead of Thursday’s meeting was “to ensure that we remain united, to cement our collective resolve, to send a powerful message that we are ready and committed to this for as long as it takes,” said his national security adviser, Jake Sullivan.

Earlier in the day, administration officials told reporters that the United States plans to take in up to 100,000 Ukrainians and other displaced people fleeing conflict in Ukraine, and will provide $1 billion in new funds. for humanitarian aid to Ukrainians and refugees in neighboring countries.

Biden administration also plans new sanctions on Russia, including Duma members and defense contractors, joins G-7 and EU on new initiative to prevent China or ‘other countries help Russian banks to do business abroad and will crack falling sales of Russian gold.

From Brussels, Biden travels to Warsaw on Friday to meet Polish President Andrzej Duda and visit US troops.

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