A Russian sailing ship due to stop in San Francisco's port on Friday unexpectedly changed course - apparently over fears it might be seized in connection with an unrelated dispute over ownership of a major Jewish library collection in Russia.

The ship, the Nadezhda, diverted to Mexico instead of making its planned ceremonial visit to the American port, apparently out of concern it could be seized in connection with an ongoing legal dispute over the Schneerson Library, of which the Brooklyn-based Chabad Hasidic movement claims ownership.

Open gallery view The Nadezhda entering Vladivostok harbor in 2004. Credit: AFP / Getty Images

The Chabad movement obtained a court judgment in the United States confirming its ownership of the library, a collection that was reportedly amassed over a period of about 200 years prior to World War II that is said to contain 12,000 books and 50,000 documents. But the Russian government disputes the authority of the U.S. court to rule on the matter. Chabad's ownership of the collection was also confirmed by a Soviet-era court, but the Soviet Union collapsed before the court's decision could be carried out.

The Nadezhda is the educational flagship of the Russian Pacific fleet and is technically owned by the Russian government. The ship was scheduled to enter San Francisco harbor at 9:30 A.M. local time, but about an hour earlier, word was sent to the ship's captain and to his hosts, apparently based on a decision by Russian government officials, that the visit was to be scrapped.

Disputed collection

Russia claims the Chabad Hasidic movement never owned the disputed collection, but it was apparently concerned that the Nadezhda could be seized to force the transfer of the library.

The American court judgment on the ownership of the library has also impeded the loan of Russian-owned artwork for display in U.S. museums, out of concern that it would be seized for the same reason.

The flap over the ship's visit not only caused embarrassment for its American hosts vis-a-vis the Russians, but also with Poland, because the ship was built in Poland and was to be greeted by members of the Polish community in San Francisco. The Russian consul, who was to attend the welcoming event, got word of the cancellation minutes before he was due to arrive at the ceremony and was reported by those present to be embarrassed and angry.

The ship was also due to make a visit to the American port of Honolulu in Hawaii, but that also appears to have been scrapped.