David Cameron has moved to reassure supporters of Israel and British Jewry following the Iranian nuclear deal struck in Geneva this week.

Speaking at a Chanucah reception in Downing Street on Wednesday evening, the Prime Minister said he shared the “scepticism and worry” felt over the interim agreement to curb Iran's nuclear programme and lift some sanctions.

Mr Cameron said he had no “starry-eyed view” of what the Iranian regime offered.

“I could go into all the details of how this interim deal means the uranium will be dealt with, how much inspection there will be… In the end it comes down to a simple judgment.

“Would it have been better to continue with a set of negotiations, hoping for one big, long-term deal but knowing that at any time you could wake up one morning with a nuclear-armed Iran?

“Or is it better now to reach an interim deal that genuinely rolls them back by several months from getting that weapon, and then going ahead with a full deal that can secure us an Iran that will never have a military nuclear capability?

“In my judgment this is the right step to take. I know there will be great scepticism, I know there will be great worry. I share that scepticism, I share that worry. I don’t have any starry-eyed view of what this Iranian regime offers.”

Mr Cameron, who lit the menorah with Chief Rabbi Ephraim Mirvis, told community leaders at the reception: “I am with you and with the Israeli people, genuinely. As far as I’m concerned, an enemy of Israel is an enemy of mine. A threat to Israel is a threat to us all.

“I can promise you this: Britain will stand with Israel, Britain will support Israel, Britain will keep the pressure up on Iran. We do not want you to have a nuclear-armed near-neighbour, a nuclear threat facing your country.

“We understand why you feel as strongly as you do about this. We share that feeling and show you our solidarity.”

Mr Cameron repeated his promise to visit Israel in 2014 and said he wanted to “show solidarity” and mark the country’s “extraordinary achievements”.

The Prime Minister also confirmed he would travel to Auschwitz next year and reflected on the “moving” dinner held by the Holocaust Educational Trust in September at which he met more than two dozen Shoah survivors.

“We should be thinking tonight about how we continue to commemorate dreadful events, in particular the Holocaust, long into the future,” he said.

“I’m very pleased that next year I will make the visit to Auschwitz myself for the first time. I so want to go, to see for myself. The privilege of going there as a head of government, as well as a private individual, is immense.”

Praising the efforts of British-Jewry, Mr Cameron said: “If you think of the contribution to the arts, to creativity, to business, to sport, to brainpower, to our communities, of those 250,000 people it really is an immense contribution. Thank you for everything you do and bring to our country.”

He said Conservative education policy would allow “more Jewish free schools, more Jewish academy schools” and make sure the community felt its children could be educated in the way parents wanted.

Mr Cameron said he felt "very much part" of the Jewish community: "In my relative research I’ve found a Levite grandmother… According, I think, to the Jewish Chronicle I’m [therefore] related to Moses."

He also joked that he had told his Liberal Democrat coalition colleagues about the miracle of Chanucah.

“I told them it’s a very important celebration because of course we are remembering the re-taking and the re-dedication of the temple. Of course there was the miracle of oil that was only supposed to last for one day, but lasted for eight days. I said it’s not to be confused with an energy policy."