The co-founder of the national Holocaust education centre has warned politicians they must be “careful” about their language at a time of rising intolerance.

James Smith, president of the Nottinghamshire based National Holocaust Centre and Museum, said politicians of all parties have a responsibility to take a strong position on all forms of intolerance and “mind their language.”

His comments come following criticism of Boris Johnson’s language over Brexit.

Mr Johnson has been accused of stoking tension with words such as “surrender” and “betrayal” to describe his opponents.

Speaking at the centre’s 24th anniversary on Sunday Mr Smith warned that the threats posed by white nationalism, antisemitism and other forms of racism and intolerance are in danger of intensifying if politicians fail to take a firm lead.

“The growth of ideas that contributed to the Holocaust, such as white nationalism and antisemitism, are alive and well today,” he said.

“A quarter of a century ago we were creating this centre as a warning from history. If we had known then that these ideas would be alive and on the rise in the UK in 2019 we would have been aghast.

“Politicians have to show leadership on this issue and they have to be careful about the language they use.”

He said where violence had been stoked around the world “you will find political leaders who have failed to rein in their language and while they are not immediately responsible there is a certain degree of cause and effect.”

He said the growing sense of intolerance in society had made the National Holocaust Centre “more determined to play its part in equipping people to see the dangers of those ideas.

“We want people to think about their views, see the dangers of prejudice and develop a greater empathy for people from other communities.”

He also urged government to invest in organisations that educate the public about the risks of intolerance.

Mr Smith said: “We have an interest in making our communities safer for everyone and it is far better to invest in prevention now than trying to address the human costs of it later.

“Finding the resources to support organisations like ours should be a priority for all of our politicians, whatever their hue.”

His comments were echoed by 87-year-old Holocaust survivor Janine Webber, who lost most of her family during the Nazi occupation of her native Poland.

Ms Webber, who is a regular speaker at the centre, was among those who attended Sunday’s anniversary event.

“There is an increase in antisemitism in the UK and the extreme right is on the rise,” she said.

“There is insecurity in the world. Some people are anti-immigrants. They are looking for a scapegoat for their problems – something that will help them get the anger off their chests. That’s why we need to keep talking about what happened.

“We, the survivors, are all getting old and we won’t last forever. We are disappearing. That is why the centre is so important.”

She said her work with the centre motivated her to “talk to people about the Holocaust so that they do not forget. It’s important that we know what happened in order to prevent it happening again, and that we encourage young people to stand up to intolerance and prejudice.”

Former Labour MP Lord John Mann, a government advisor on antisemitism, also attended the event which featured a service of memorial and rededication and a live sculpting event with Frances Segelman.

The sculptor created a bust of Marina Smith MBE, co-founder of the centre, in recognition of her support for the centre’s survivor team.

Ms Segelman said she was honoured to be sculpting Ms Smith at Sunday’s event.

“Marina and her family have done such incredible work at The National Holocaust Centre and Museum,” she said.

“The centre is a vital reminder of what can happen and must never happen again.”