The World Jewish Congress (WJC) has written to each of the Swiss cantons asking them to check the provenance of works of art bought between 1933 and 1948, according to a report in the magazine "Facts".
According to the magazine, the WJC also stated in its letter that it was disappointed by the lack of progress by the Swiss in tracking down works of art stolen by the Nazis.
The New York-based body instructed the Geneva law firm Lalive & Associates to act for it in this matter and to draw up the letter.
According to Andrea Rascher, from the Federal Office of Cultural Affairs, investigations were carried out four years ago. "These found that Switzerland's art collections contained two works belonging to Jewish art lovers," she told the magazine.
Cäsar Menz, director of the Art and History Museum in Geneva, said he had learned about the WJC letter before the start of the summer, but stressed that the museum had nothing to hide.
"During the 1930s and 1940s, our museum was facing a serious financial crisis and did not was make a lot of acquisitions," he said.
The World Jewish Congress agreed a $1.25 billion (SFr2.11 billion) settlement in 1998 with Switzerland's two biggest banks - UBS and Credit Suisse - to settle the claims of Holocaust survivors who held assets in Switzerland during the Second World War.
swissinfo with agencies