UPDATE 1-Congo says most mining firms to stay despite review

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KINSHASA, Nov 6 (Reuters) - Democratic Republic of Congo's mines minister said on Tuesday most mining companies operating in the country would remain in the long term despite a review of contracts being carried out by the government.

"It is expected that after all irregularities have been corrected, the great majority of companies currently in the Democratic Republic of Congo will remain in the country for the long term," Mines Minister Martin Kabwelulu said in a statement.

The government set up a mining commission earlier this year in the vast former Belgian colony to bring contracts, most of which were negotiated during a 1998-2003 war and a subsequent three-year transition period, up to international standards.

A leaked preliminary report seen by Reuters on Saturday said the panel recommended that 61 contracts needed to be renegotiated or cancelled.

The contracts being reviewed included deals with international firms such as Freeport McMoRan Copper & Gold Inc (FCX.N), BHP Billiton (BHP.AX) and Nikanor NKR.L.

The central African country's government said it regretted the leak and sought to reassure the companies involved.

"The speculation is not based on any official document but on a leak of an early draft from within the commission," the statement said. "The government deplores the leaking of this draft and the uncertainty that it has understandably created." (Reporting by Joe Bavier; Writing by Nick Tattersall; Editing by Peter Blackburn)