BHP Group Limited (ASX:BHP) is asking the short-listed bidders for its two Queensland coal mines on offer to resubmit offers on September 25 after final bids landed last month. DataRoom revealed earlier that suitors had until the end of the month to lock in funding for a transaction and that Whitehaven was firming as the favourite to win the contest. Left in the contest are Whitehaven Coal Limited (ASX:WHC), bidding for both assets, Peabody Energy Corporation (NYSE:BTU) bidding for the Daunia mine, BUMA bidding for the Blackwater mine and Stanmore Resources Limited (ASX:SMR) bidding for Daunia.

Sources say Stanmore Coal, which is sourcing debt to fund its bid with help from Grant Samuel, is believed to be the most conservative of the bidders when it comes to price. UBS has put a USD 2.5 billion value on Blackwater, which analysts say has a 50-year mine life, and a USD 800 million value on Daunia, which they believe has a 17-year mine life, with USD 1 billion of rehab liabilities on the former and USD 250 million on the latter. Some Whitehaven shareholders are warming to the prospect of the coal miner buying both Daunia and Blackwater in a deal that may top USD 3 billion.

DataRoom first revealed Whitehaven was bidding for both mines on August 24, and the company confirmed this on Monday. It also reiterated comments made while reporting its results last month that it had suspended its share buyback as it considered growth opportunities.