LONDON (AP) _ During World War II the Nazis looted at least $550 million in gold _ now worth more than $6 billion _ from German-occupied countries and stashed most of it in Swiss banks, Britain says.

The United States and its allies, who knew about the plunder, recovered only a small portion of the pilfered gold, much of which had been stolen from Jews, the Foreign Office said Tuesday.

The announcement prompted renewed calls from Jewish groups for compensation. They maintain Swiss banks have billions of dollars that was either smuggled out of occupied territories by Jews and never returned to them, or stolen from them by the Nazis.

``This is stolen property, it does not belong to the Swiss. It should go back the the survivors of the Holocaust,'' said Greville Janner, a Jewish lawmaker who chairs the Britain-based Holocaust Educational Trust.

``For the first time, previously unpublished Bank of England documents reveal how British officials turned a blind eye to the transactions because they were desperate not to upset neutral countries we needed to trade with.''

The Foreign Office report does not answer Janner's questions about whether any of the looted gold found its way to Britain.

But Janner hopes Holocaust survivors can use the information to support claims for compensation against the Swiss.

Swiss officials had no immediate comment.

``The report is being studied at our headquarters in Bern,'' said a spokeswoman for the Swiss Embassy in London.

The Foreign Office searched British archives after opposition legislator Janner asked Foreign Secretary Malcolm Rifkind about the gold in June.

Its 23-page report is potentially embarrassing to governments of the former Allies, which knew where the money was but never disclosed the information.

The report said contemporary documents reveal that during postwar negotiations between Allied governments and the Swiss, a delegate from the Swiss National Bank, the country's central bank, acknowledged that his country had ended the war with $500 million of Nazi gold.

Previous estimates by the Holocaust Educational Trust had put the figure at up to $398 million in gold. Jewish groups say that even the lower figure far exceeds the amount of gold reserves Germany would have been able to hold legitimately.

The Allies later did a deal with the Swiss to accept repayment of $60 million, believing it was the most they could get, the Foreign Office report said.

They waived all further claims against the Swiss government and the Swiss National Bank in connection with gold acquired during the war. It is not clear how much, if any, of this money was repaid to Holocaust survivors.

The Foreign Office said the Allies ``knew that large amounts of gold were exported from Germany to the neutral countries such as Portugal and Switzerland, in payment for goods and foreign exchange'' during the war.

``They also suspected that the Nazi regime used these channels to conceal looted gold and other property,'' the report said.

``Though the Allies made every effort at the end of the war to seek out German assets, at home and abroad, for restitution or use as reparations, they knew that it was impossible to track down all the gold looted by Germany and that those countries _ let alone individuals _ who had lost everything would never be repaid fully,'' it said.

In May, Swiss bankers agreed to relax their stringent secrecy laws to allow a search for money deposited by Jews who died in the Holocaust.

Swiss bankers say they had found $34 million in unclaimed accounts allegedly belonging to Holocaust victims.

Today, Hanan Ben Yehuda, treasurer of the Jewish Agency, sent a letter to Swiss President Kaspar Williger urging him to ``intervene personally'' to find the deposits soon, ``before the aged survivors of the Holocaust end their days in the shadow still casting its pall over the modern Swiss nation and its international reputation.''