A Chinese company and private equity firms are among the groups expected to submit final bids for Rio Tinto's borates and talc units, according to sources close to the matter, in deals potentially worth over $1 billion.

Final offers for Rio Tinto's (RIO.AX) (RIO.L) borates and talc units, which the mining giant is selling to pay down nearly $40 billion in debt, are due within a week, according to the sources.

The world's No.2 miner-- which is axing 14,000 jobs and cutting capital expenditures by more than half-- is seeking buyers for a host of core and non-core assets after bigger rival BHP Billiton (BHP.AX) (BLT.L) ended its $66 billion hostile takeover bid in November.

What I've heard is that final bids are imminent, perhaps by the end of next week, one source told Reuters.

The sources did not disclose the names of the Chinese bidder or the private equity parties. The sources also did not want to be named because the auction is at a sensitive stage.

(Reporting by Joseph Chaney and Michael Flaherty; Additional reporting by Michael Erman in NEW YORK and Quentin Webb in LONDON; Editing by Jonathan Hopfner)

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