Russian President Vladimir Putin said Tuesday he refused to return a historic but disputed Jewish archive to the United States because doing so would "open a Pandora's box".
He spoke after a US judge slapped a daily fine of $50,000 (37,500 euros) on Moscow last month for its failure to comply with a 2010 order to return the sacred texts.
Putin's international cultural cooperation representative Mikhail Shvydko said at the time that the ruling "doomed" the chances of the archive ever being sent to the United States.
Speaking at a Moscow meeting on inter-ethnic issues, Putin called the ruling "unjust" and proposed instead to display the collection in Moscow.
"If we open a Pandora's box today and begin to grant such claims, then there won't be an end to such requests and it is unclear what they will lead to," he said in televised remarks.
"Maybe one day we will be able to do so but in my opinion, right now we are simply absolutely not ready for it. It is not possible."
He suggested the texts be displayed at the Jewish Museum and Tolerance Centre, which opened in November and is one of the world's largest Jewish museums.
The archive -- referred to in Russia as the Schneersohn Library in honour of its original owner Rabbi Joseph Isaac Schneersohn -- was split up and partially nationalised by the Soviet Union in 1918.
The other part was taken out of Russia and ended up in Germany where it was seized by Soviet troops at the end of World War II in 1945.
Most of the 12,000 texts and 50,000 documents it contains have since been transferred to the Russian military archive and state library.
Officials there said last month that they had no intention of parting with a collection gathered in the 18th century and regarded with veneration by Hasidic Jews who populated eastern Europe and have since largely settled in New York.
The dispute has frozen cultural exchange programmes between the two old Cold War rivals and as a result, touring exhibitions of such great museums as the Hermitage and the Tretyakov have bypassed the United States.
The US State Department has argued that decisions of the kind issued by the District Court complicated both the case and bilateral ties.
Since Putin's return to the Kremlin for a third term in May, Russia and the United States have been at odds over a growing number of issues.