The firm, International Diamond Industries, was welcome to join other bidders as contracts for the diamond exports are now offered on the free market, said Congo's vice minister of mining, Mbaka Kawaya.
Congo is the world's third-largest exporter of diamonds.
Exports of mostly industrial-quality diamonds accounted for about 70 percent of the Central African nation's total export revenues in 1999. The U.N. inquiry concluded the deal had the unwanted effect of driving much of Congo's diamond trade underground depriving the government of its revenue. A spokesman for IDI insisted on Saturday that the firm had paid the full amount it promised in the contract, although he wouldn't say how much that was. May claimed Congo had been under pressure from IDI's competitors and the International Monetary Fund to annul the deal. IDI and government officials had been in talks to amend the terms of the contract when Congo announced it was canceling it, he said.