All five living prime ministers have backed the building of a Holocaust memorial next to the Houses of Parliament, with Theresa May saying it is the right thing to do.
Mrs May has joined with four former occupants of Downing Street – David Cameron, Gordon Brown, Tony Blair and John Major – to voice their support for the project.
The decision to locate the Holocaust Memorial and Learning Centre in Victoria Tower Gardens has drawn criticism in some quarters, including from Historic England and The Royal Parks, which looks after the site.
There are concerns that it could obscure views and restrict the public space in the area.
But Mrs May said delivering on the project was a “sacred, national mission”.
It will be dedicated to the six million Jewish men, women and other victims murdered by the Nazis.
The prime minister said in a video message which will be played at a Holocaust remembrance ceremony in London: “By putting our National Holocaust Memorial and Education Centre next to our parliament, we make a solemn and eternal promise that Britain will never forget what happened in the Holocaust.
“Seeing this through is a sacred, national mission.
“In the face of despicable Holocaust denial, this memorial will stand to preserve the truth forever.
“And this education centre will ensure that every generation understands the responsibility that we all share – to fight against hatred and prejudice in all its forms, wherever it is found.”
Labour’s Tony Blair, who was in office from 1997 to 2007, appeared to deliver a rebuke to current party leader Jeremy Corbyn in his message.
He said: “Antisemitism and hate did not end in 1945.
“Unfortunately today some of this poison is back from the political fringe to parts of the political mainstream.
“So, it’s absolutely right that this new national memorial is situated right next to parliament.
“So we can show what happens when racism and prejudice go unchecked.”
Mr Corbyn has faced accusations of not doing enough to tackle claims of antisemitism in the Labour Party.
The party has rejected this, saying Mr Corbyn takes all complaints seriously and is committed to “challenging and campaigning against it in all its forms”.