Flicking through the Sunday Times Rich List last weekend, I found myself pulling the usual trick of looking for Jewish names (only Jews and antisemites do this as far as I am aware).

There were some familiar faces: the old money of the Rothschilds and the Wolfsons, the nouveau millions of Philip Green and Richard Desmond. But my faultless Jewdar also picked up some less familiar figures. Right at the top, the richest person in the country was Len Blavatnik, a Russian-American oligarch who made his money in oil. There was also Eugene Shvidler, an associate of Roman Abramovich, and the Finnish Poju Zabludowicz. Other less familiar names were Mark Scheinberg, an Israeli-Canadian who has made billions in online gaming, and Israeli Teddy Sagi, who has done the same.

London attracts wealthy Jewish émigrés from Russia, the former Soviet Union and Israel for the same reasons other billionaires come here. It is perfectly located and culturally kitted out for the international rich: high-end property, endless first-rate restaurants and a favourable business environment.

But from a Jewish perspective, these new residents represent more than just rising property prices and a boom in the private jet market. They represent a once-in-a-generation opportunity to inject new life into the community.

The old tradition of Jewish philanthropy in this country has faded somewhat, as the Montefiores, Rothschilds and Wolfsons have been swallowed into the establishment. But these men can be the new Rothschilds. They have bucketloads of surplus cash, the desire for affirmation and respectability that often motivates new money and London as their home.

The benefits of this new relationship are already being felt in Britain. Eugene Shvidler has put millions into the rebuilding of Edgware Jewish Primary School, now known as Beit Shvidler Primary School. Len Blavatnik put £70m into building the new Blavatnik School of Government at the University of Oxford. Other oligarchs such as Mikhail Bezeliansky and Gennady Bogolyubov have supported Jewish causes in Britain. But these men are far too canny to just hand out funding to any schnorrer who knocks on their door.

"These men are smart. They want to know what their money will be used for," says Semyon Dovzhik, a Russian-Israeli journalist living in London. "You have to offer them something. They want recognition for their donation" (thus the renaming of the primary school).

But it's also important to recognise that the oligarchs represent only a tiny percentage of the Russian Jewish population in London, who have much to offer beyond their money. There are as many as 10,000 Russian-speaking Jews in London today.

There are Russian-dominated synagogues now active in Belgravia and in West Hampstead, where Rabbi Dovid Katz has started a Chabad chapter. "There is a real desire among Russian Jews for more interaction with the community here," says Dovzhik.

"Many of them are secular, so they don't necessarily want to join a synagogue. But in Russia many of them were involved in community organisations and would send their children to summer camps. They'd like to do that here, too." And it's not just Russians. French Jews have been coming to London in their thousands, partly to escape Francois Hollande's economic mismanagement, but also in response to the wave of fatal antisemitic attacks that have taken place. There are as many as 20,000 French Jews in London now, who have helped turn the city into Paris's 21st arrondissement. In Notting Hill, there is a growing community of American Jews, drawn to London's financial markets. And more than 10 per cent of London's Jews are Israeli.

Just as London has become a global city, so Jewish London has, too. Many of these new Jewish communities are quite self-sufficient, but the British Jews of north-west London should do their utmost to reach out to the new neighbours. As well as philanthropy, these new Jews can bring to the community different traditions, émigré sophistication and a more cosmopolitan feel. Britain has sometimes felt like a backwater in the Jewish world, slumped between the dynamism of America and Israel. These new arrivals can help change that.

Many young Jews despair of finding a suitable shidduch in London - who wants to marry someone they went on Tour with? But there are now thousands of new young Jewish families. Many of us living up in the north-west London bagel belt may hardly have noticed this new influx. It's time we did. Jewish London's gone global.