Joe Biden
Joe BidenOfficial White House Photo by Adam Schultz

U.S. President Joe Biden got into a heated exchange with a reporter over the topic of Russia sanctions on Thursday.

"Sir, deterrence didn’t work. What makes you think Vladimir Putin will alter course based on the action you’ve taken today," the reporter asked Biden at a press conference during the NATO summit in Brussels.

"Let's get something straight," Biden answered back. "You remember, if you covered me from the very beginning, I did not say that in fact the sanctions would deter him. Sanctions never deter. You keep talking about that. Sanctions never deter."

"The maintenance of sanctions, increasing the pain and the demonstration [is] why I asked for this NATO meeting today, is to be sure that after a month, we will sustain what we're doing, not just next month, the following month, but for the remainder of this entire year," Biden said.

The president added that the "single most important thing is for us to stay unified" and said that the international community needs to "continue to focus on what a brute [Putin] is, and all the innocent people's lives are being lost and ruined."

"We have to stay fully, totally thoroughly united," Biden said.