Boris digs in as JCC starts its £50m building

Dame Vivien said it had been "a long, long journey" since she first proposed a centre for London nine years ago after seeing JCCs at work in America.

"Everybody was trying to persuade me it would never work, we would never find anywhere and the whole thing was ridiculous," she recalled.

She paid special tribute to Chief Rabbi Lord Sacks for his encouragement, without which, "I might have given up". In turn, she had promised him the centre would have no religious ceremonies, be kosher and uphold Jewish ethics "to the height".

Dame Vivien expressed delight at the attendance of rabbis from across the religious spectrum, demonstrating the project's community-wide appeal.

Chief executive of JCC ventures, Nick Viner,who came on board five years ago, was also "rubbing his eyes".

Historically, British Jewry had lacked "the confidence and exuberance of our cousins across the Atlantic, but that is beginning to change and we are contributing to change", he said.

"We are confident that people will want to keep coming back and before long… the building will earn a place in their hearts, even becoming their second home."

The 35,000 square-foot centre will house, among other things, a 60-seat cinema, arts and dance studios, craft rooms, a hall, a nursery and a kosher café. The groundbreaking was heralded by a blowing of the shofar by Martin Landau.

After a short performance from the Akiva school choir, the Chief Rabbi said: "On their faces we saw the future of our Jewish community and it is smiling."