The book gives signatories the opportunity to pledge their commitment to challenging all forms of prejudice. It has been signed by the majority of MPs.

Cameron paid tribute to the work of the the Holocaust Educational Trust during Prime Minister's Questions.

He said: "With each year that passes since the end of the Holocaust, we have a greater responsibility than ever to remember the dreadful events that took place.

"By learning from history, we must pledge that nothing like this ever happens again."

Opposition leader Ed Miliband, who has spoken publicly of his parents' escape from the Nazis, added a message to the book.

He wrote: "It reminds us that we must never forget the terrible genocide perpetrated against Jews.

"We owe it to all those who perished to remember and speak up against antisemitism.

"We must speak out against injustice and bigotry wherever we find it."

Signing the book at Downing Street, Mr Cameron said: "Last year I had the privilege of meeting an extraordinary, courageous woman.

"Trude Levi was just 20 when she was ripped from her family.

"She was forced on a journey that can only be described as hellish, through concentration camps, work camps and death marches.

"She saw and suffered some unspeakably evil things, but she survived to tell her story and pass it on to the next generation.

"It is so important that stories like Trude's continue to be heard, read and spoken about.

"That way the brutal truth of the Holocaust can never be dimmed.

"And that is why Holocaust Memorial Day matters so much."