French Finance Minister Francis Mer has rejected a court request to declassify documents related to the controversial 1991 sale of six frigates to Taiwan, sources close to the inquiry said Friday.

Mer's decision will keep the lid on information related to the sale of six Lafayette warships, built by Thomson CSF, for 2.8 billion dollars (2.9 billion euros), a deal that strained France's relations with China.

The transaction has also sparked allegations of wide-ranging corruption in both Paris and Taipei, with officials on both sides charging that politicians and military leaders pocketed millions of dollars in kickbacks from the sale.

An official inquiry found that Taiwanese politicians and military leaders took 26.75 million dollars in kickbacks and 28 people -- 13 of them military officers -- have been jailed for bribery and leaking military secrets.

The scandal broke after the death of Taiwanese naval captain Yin Ching-feng, head of the navy's acquisitions office, whose body was found floating in the sea off the island's east coast in 1993.

It has been alleged Yin was murdered as he prepared to blow the whistle on rampant corruption in the military -- including the deal with Paris.

Also implicated is former French foreign minister Roland Dumas, convicted last year of taking illegal gifts from the formerly state-owned oil company Elf.

Dumas' former mistress, Christine Deviers-Joncour, was hired by Elf to sway the minister's decisions, and a large part of her salary was aimed at getting Dumas to drop his opposition to the frigate deal.

The then French president Francois Mitterrand eventually approved the sale but Dumas insists he remained opposed to the sale.

Two Paris judges investigating the sale and the deaths of several people connected to the scandal have asked that Thomson documents considered "official secrets" be declassified.

Six months ago, former finance minister Laurent Fabius, who served in the recently ousted Socialist-led government of Lionel Jospin, rejected the judges' request.

Police searched the headquarters of Thomson CSF, which has since been renamed Thales, on Tuesday in connection with the probe, seizing a number of documents.

With acknowledgement to Sapa.