People insured by Blue Cross Blue Shield of Texas will not have access to in-network coverage at Texas Health Resources next year unless an agreement is reached before the end of the year.

The insurer and health system's lengthy negotiations have not resulted in an agreement on a new contract, they said. The provider will be out-of-network starting on Jan. 1. THR is a nonprofit health system based in Arlington that serves more than 7 million people in 16 North Texas counties.

It's not the first time Blue Cross has had contract negotiations go down to the wire.

In April, just weeks before its contract was about to end with the nation's top hospital operator, HCA, the two came to an agreement. A failed deal would have left millions out-of-network at dozens of hospitals and outpatient centers, and doubled out-of-pocket costs for those patients.

THR and Blue Cross also found themselves in a stalemate in late 2010. That time they reached an agreement, however.

"As one of the major insurance companies in the state, we have been tasked with trying to bring some sanity to the price structure," said Dr. Paul Hain, market president for Blue Cross in North Texas. "Negotiations are difficult when providers demand huge increases ... because the rates are already way too high," he said.

In a statement late Monday, THR's chief executive officer, Barclay Berdan, said the provider is committed to reaching an agreement, but "we do not want to negotiate this contract renewal in public."

According to Hain, THR requested an increase of $57 million. THR would not confirm the amount of the increase, but Berdan said that any figure from Blue Cross "should be taken with a truckload of salt."

THR has more than 350 points of access in North Texas, including 25 hospitals, outpatient centers, doctors' offices and imaging centers. The system recently acquired 27 free-standing emergency rooms from Adeptus.

Blue Cross Blue Shield, the only health insurer to offer plans in all 254 counties in Texas, is the state's largest insurer. It has contracted with several other providers in D-FW, including Baylor Scott & White Health, HCA, Methodist Health, UT Southwestern and Children's Health Dallas.

For individuals purchasing health insurance on the marketplace, open enrollment began on Nov. 1. It is unclear what will happen to consumers who selected a Blue Cross plan thinking that THR would be in-network.