The United States’ White House Press Secretary Sean Spicer on Tuesday apologised for his remarks comparing Syrian President Bashar al-Assad with German Nazi dictator Adolf Hitler. “We didn’t use chemical weapons in World War II. You had someone as despicable as Hitler who didn’t even sink to using chemical weapons,” he had said at a press briefing earlier in the day, according to The Guardian.

After reporters had pointed out the Hitler had killed millions of Jews in gas chambers during the Holocaust, Spicer had appeared to fumble with a clarification and said, “I think when it comes to sarin gas, he [Hitler] was not using the gas on his own people the same way Assad is doing.”

During an interview on CNN in the evening, the press secretary tried to clarify his remarks and apologised. “I was obviously trying to make a point about the heinous acts that Assad had made against his own people last week, using chemical weapons and gas. Frankly, I mistakenly made an inappropriate and insensitive reference to the Holocaust, for which there is no comparison. And for that, I apologise,” Spicer said. “It was a mistake to do that.”

Spicer’s remarks came on the first day of Jewish holiday Passover, one of the holiest days in Judaism that commemorates the liberation of Jews from slavery in Egypt.

Before appearing on CNN, Spicer had issued a statement trying to clarify his comments. “In no way was I 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,” he had said.

The National Jewish Democratic Council of US called the press secretary’s comments “inappropriate and insulting” and said, “Hitler used chemical weapons. Period. No amount of clarification or walking back from the press secretary’s office should be accepted for Spicer’s horrific mistake.”

The Democrats were quick to condemn his remarks. Senator Brian Schatz and from Hawaii and a member of the Senate’s Foreign Relations Committee Ben Cardin, who are both Jewish, criticised his remarks. “I find nothing funny about the press secretary bungling Holocaust history. Because I’m not sure they should get the benefit of the doubt.” Cardin, on the other hand, asked Spicer to “get a refresher history course on Hitler”. House Democratic leader Nancy Pelosi demanded that Spicer be fired for “downplaying the horror of the Holocaust”.

On April 7, the United States had carried out targeted missile strikes in Syria in response to the deadly chemical attack that killed dozens in the country’s rebel-held Idlib province. The Syrian Army has said that the strike had killed six personnel and caused “big material losses. Hours before launching the missile strike, US President Donald Trump had said that the poison gas attack had “crossed a lot of lines” for him.