And another - reaction is very bad. We might be in for a...

And another - reaction is very bad. We might be in for a thrashing on Tuesday unless something very significant happens in the meantime to reverse this sentiment.

DIVERSIFIED miner OZ Minerals shocked the market yesterday by placing itself in a trading halt.

The troubled miner admitted it was struggling to refinance $US560 million ($856 million) worth of debt.

The miner, which has already been forced to cut staff, curtail production and review all operations because of the commodity price slump, was seeking to refinance two debt facilities by tomorrow.

In a note to the Australian Securities Exchange yesterday morning, the Melbourne company said it had agreed with lenders it would refinance two facilities, one of $US420 million and one of $US140 million, by November 30.

It now wants an extension until January 31 to negotiate a proposed syndicated facility.

"We have requested a response to this request from the lenders during the course of today," it said.

Until late on Thursday night the miner thought it had reached an agreement on the extension but one lender, out of a syndicate of seven, put caveats on the deal were unworkable, an OZ Minerals spokesman said.

He would not be drawn on options the miner may have to consider if the refinancing with the banks failed.

"We are focused on concluding this process," he said.

OZ Minerals's announcement followed the surprise move by CopperCo on Thursday night to call in the administrators and receivers because it could not raise about $50 million to service a debt.

Analysts said banks closing their doors to debt refinancing raised concerns that they were pulling the rug from under well-run mining operations, which could destabilise the resources sector.

Questions were also raised about OZ Minerals's seemingly 11th-hour decision to alert the market to the refinancing crisis. Analysts claimed it was a shock for the announcement to be made only two days before the November 30 deadline.

When the company was formed in June through the merger of Oxiana and Zinifex, it was flagged that the debt facilities would need to be renegotiated in November, the OZ spokesperson said. OZ Minerals has been one of the hardest hit high-profile miners since the merger, which at the time was hailed as forming a new mining major in the sector.

One analyst said it was an unfortunate turn of events for the miner.

"You have a company, that once had very strong cashflows and now it has what can only be negative cashflows and a position where a significant portion of debt needs to be refinanced or extended in an environment where the credit markets are frozen," he said.

"This is a working capital issue for which 12 months ago any number of banks would have stepped up and said here is the money."

Another analyst who covers the company said the miner could face further difficulties if the refinancing was not secured.

If the refinancing "doesn't get under way, it is going to be in trouble and that will be a problem", he said.