The world marks Holocaust Remembrance Day Saturday, the anniversary of the liberation of the Auschwitz Nazi death camp in 1945.

The U.S. Holocaust Memorial Museum in Washington hosted officials from around the world to remember the genocide.

European Union Ambassador David O’Sullivan said that museums remembering the Holocaust are essential for future generations to learn about the past atrocities.

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“The new generation also needs people, stories and places to keep the memory alive. To make sure we keep the promise made at the end of the Holocaust — Never Again,” O’Sullivan said.

Museum officials also read a letter from Dr. Muhammad Al-Issa, secretary-general of the Muslim World League based in Saudi Arabia, who wrote, “Who in their right mind would accept, sympathize or even diminish the extent of this brutal crime?”

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First lady Melania Trump was among those who toured the U.S. Holocaust Memorial Museum Friday and tweeted that she experienced a “powerful and moving tour.” She posted a photograph of her lighting a candle at the Prayer Wall.

On Saturday in the Polish capital of Warsaw, U.S. Secretary of State Tillerson paid tribute to Holocaust victims by placing a wreath and making remarks at the Warsaw Ghetto Uprising Monument.

“On this occasion it reminds us that we can never, we can never, be indifferent to the face of evil. The Western alliance which emerged from World War Two has committed itself to ensuring the security of all, that this would never happen again.”

The U.N. Security Council announced Friday that its members will visit the U.S. Holocaust Museum on Monday as part of a trip to Washington, where they will also have lunch with President Donald Trump.

The White House on Friday recognized International Holocaust Remembrance Day with a message that said, “We acknowledge this dark stain on human history and vow to never let it happen again.”

The statement specifically mentioned the 6 million Jews killed by the Nazis, following criticism last year that it made no mention of Jews in its statement.

“Tomorrow [Saturday] marks the 73rd anniversary of the liberation of Auschwitz-Birkenau, the Nazi death and concentration camp in Poland,” the statement said.

“We take this opportunity to recall the Nazis’ systematic persecution and brutal murder of 6 million Jewish people. In their death camps and under their inhuman rule, the Nazis also enslaved and killed millions of Slavs, Roma, gays, people with disabilities, priests and religious leaders, and others who courageously opposed their brutal regime,” the statement said.

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Last year, the White House defended its omission of Jews from the statement with Hope Hicks, now the White House communications director, saying that “despite what the media reports, we are an incredibly inclusive group, and we took into account all of those who suffered.”

At the United Nations, U.N. Secretary-General Antonio Guterres said in a statement Friday that “decades since the Second World War, we see the persistence of anti-Semitism and an increase in other forms of prejudice.”

He said the world remembers the 6 million Jews who died in the Holocaust and said, “All of us have a responsibility to quickly, clearly and decisively resist racism and violence.”
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