One in 20 British adults does not believe the Holocaust took place while eight per cent believe the number of Jews murdered is exagerated, a shocking poll has found.

The research, published to coincide with Holocaust Memorial Day on Sunday, also shows that nearly two thirds of people - 64 per cent - either do not know how many Jews died or "grossly underestimate" the figure, with 19 per cent of people believing fewer than two million died.

This is less than a third of the actual figure of six million.

Olivia Marks-Woldman, chief executive of the Holocaust Memorial Day Trust which surveyed 2,000 people for the research, said: "Such widespread ignorance and even denial is shocking."

She added: “The Holocaust threatened the fabric of civilisation and has implications for us all... Without a basic understanding of this recent history, we are in danger of failing to learn where a lack of respect for difference and hostility to others can ultimately lead.

"With a rise in reported hate crime in the UK and ongoing international conflicts with a risk of genocide, our world can feel fragile and vulnerable. We cannot be complacent."

Shoah survivor Steven Frank, who was among just 93 children who survived the Theresienstadt camp, said the scale of ignorance was "terribly worrying".

“People don’t have a solid understanding of what happened during the Holocaust and that’s one of the reasons I am so committed to sharing what happened to me.

“At one of my talks, I met someone who said the Holocaust didn’t happen. The only way to fight this kind of denial and antisemitism is with the truth – I tell people what happened, what I saw and what I experienced. Education is so important. If we ignore the past, I fear history will repeat itself.”

A total of 83 per cent of respondents said it was important to know about the Holocaust while 76 per ent said more had to be done to educate people.

Ms Marks-Woldman noted that 25 per cent of people believed the Holocaust could never happen again but added: “Genocides have been carried out across the world in the last 70 years.

"Each of us has a responsibility to know what happened, and the need for Holocaust Memorial Day has never been so pressing.”

Dr Joe Mulhall, a reearcher and HMDT trustee, said: "As time passes we have fewer and fewer people who witnessed the horrors of the Holocaust first-hand...

"The best way to fight back against Holocaust denial wherever it rears its head is awareness and education."