The Duke of Edinburgh has been unwittingly drawn into a row over a piece of prime Jerusalem real estate by Zalmi Unsdorfer, the chairman of Israel's Likud-Herut party in Britain.

The row centres on the famous Russian Compound in the heart of Jerusalem. One part of it is called Sergei's Courtyard. Built in 1890 for the benefit of pilgrims visiting Palestine, it was named after Tsar Alexander II's son Sergei Alexandrovich, head of the Imperial Society of Russian Orthodox Christians in the Holy Land.

London-based company director Mr Unsdorfer and some of his political allies in Israel have become increasingly angered over the fact that Israel has agreed to give back the Russian Compound to its original owner, Russia.

Now Mr Unsdorfer has sought the help and support of Prince Philip, who is reputed to be the closest surviving heir of Grand Duke Sergei.

In a letter, he told the Prince: "It has been widely held that, as Sergei Alexandrovich died without children, you are probably the only truly legitimate claimant to this Romanov family property. I have it on good authority that a single letter from Your Royal Highness would halt this nefarious transaction in its tracks and probably stall it for many years to come."

Israel acquired the Compound in 1964 for $3.5 million (about £1.9 million at today's exchange rates) in what became known as the "Orange Deal" - lacking hard currency, Israel was alleged to have paid in citrus fruit. It was used by the British during the Mandate, as its centre of government and currently houses a number of Israeli government offices and a courthouse.

Three years ago, Vladimir Putin, then Russian president and now prime minister, laid claim to Sergei's Courtyard as the property of the Russian Orthodox Church. Israel has been involved in talks for its return ever since. According to a report in the Jerusalem Post, Sergei Stepashin, head of the Imperial Orthodox Palestine Society, suggested that Russia's oligarchs Roman Abramovich and Arkady Gaydamak had agreed they would pay for a new courthouse and that Israel would receive other compensation, but there has been no confirmation of the deal nor any figures made public.

Commenting on the proposal to return the Russian Compound, Mr Unsdorfer said: "A lot of people in
Israel are very angry about this and want it stopped."

In his letter to Prince Philip, he says: "Lawyers appealing this move maintain that Mr Olmert's government has even less legal right to dispose of this property than Mr Putin has rights to claim it back for Russia.

"Before the fall of the Berlin Wall, Israel absorbed over a million Russian Jews who fled Soviet oppression. Now that it seems Russia is reverting to its Cold War ways, it would be deeply offensive to these émigrés to see a potential KGB base being gifted to Mr Putin in the heart of their adopted capital city."

Mr Unsdorfer suggested that the Prince's intervention could lead to the property being placed in a special trust, prior to becoming a heritage centre for the many Russian pilgrims who still visit Jerusalem every year.

The suggestion has not yet been rejected; he has received a reply from an aide of the Prince, stating: "I am currently making enquiries on behalf of Prince Philip, after which I will be in touch."

Buckingham Palace would not comment on "private correspondence".