The British ambassador to the U.S. told a Washington audience Tuesday that President Donald Trump is right in calling Russian President Vladimir Putin "crazy."

Ambassador Peter Mandelson told an Atlantic Council lecture audience that Trump's characterization of Putin over the weekend as "crazy" is accurate.

Trump posted late Sunday in response to building missile and drone attacks on Ukraine that "I've always had a very good relationship with Vladimir Putin of Russia, but something has happened to him. He has gone absolutely CRAZY!"

The Hill reported that Mandelson carried on where Trump left off. "I mean crazy in his indifference to international opinion, crazy in his disrespect to the president of the United States."

The ambassador said few could be supportive of Putin's approach, "Notably gone crazy in the continuing death and destruction that he is visiting upon Ukraine and his people."

Mandelson also said the death and destruction should be disturbing to everyone. "This weekend saw the biggest single bombing raid of Ukraine, killing so many Ukrainians sleeping in their beds that we've seen since the invasion began."

He said Putin raises a question that has already answered itself. "Is this a man who's looking for peace? Doesn't look like it to me."

Mandelson also told the lecture audience that Trump's demand that NATO nations pay more for their defense is appropriate. "I think President Trump is doing Europe a favor by confronting us with this reality," he said. "The United States is the U.K.'s closest defense and security ally. We must become less dependent on America, while remaining inseparably linked to America, a distinction that I underline of critical importance."

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