White House press secretary Sean Spicer apologized Tuesday for “insensitive” remarks in which he seemed to favorably compare Adolf Hitler’s actions during the Holocaust to atrocities carried out now by president Bashar al-Assad in Syria, according to Agence France-Presse (AFP) news agency.

During a White House briefing Spicer sought to intensify criticism of Assad, painting the Syrian leader’s suspected use of sarin nerve agent against civilians last week as historically evil.

“You had someone as despicable as Hitler who didn’t even sink to using chemical weapons,” the spokesman said during a White House press briefing.

Spicer’s comments came during the Jewish festival of Passover.

But his latest claim brought anger from across the political spectrum and looks of astonishment from the assembled White House press corps, who offered Spicer a chance to clarify.

“I think when you come to sarin gas, there was no -- he was not using the gas on his own people the same way that Assad is doing,” Spicer said, returning to the subject.

As journalists shouted “what about the Holocaust?” Spicer continued, “I think there is clearly... I understand the point, thank you, thank you I appreciate that.”

Hitler “brought them into the Holocaust centers, I understand that. But I’m saying in the way that Assad used them, where he went into towns, dropped them down, to innocent -- into the middle of towns, it was brought... so the use of it, I appreciate the clarification, that was not the intent.”

A few hours later, Spicer appeared on US television expressing regret for the comments.

“Frankly, I mistakenly used an inappropriate and insensitive comment about the Holocaust and there is no comparison,” he said. “For that I apologize. It was a mistake to do that.”

In an earlier written clarification, Spicer said he was “in no way... trying to lessen the horrendous nature of the Holocaust.”

“I was trying to draw a distinction of the tactic of using airplanes to drop chemical weapons on population centers. Any attack on innocent people is reprehensible and inexcusable,” he explained.