The Foxwoods Resort Casino, which is in default on a $1.7-billion debt package, faces serious financial challenges in 2015 if it is unable to negotiate a new agreement, auditors warned.

In the casino’s annual audit, auditors Deloitte said the casino’s operations would be negatively affected if its lenders exercise their remedies, The Day of New London reported.

"These matters raise substantial doubt about the Enterprise’s ability to continue as a going concern," Deloitte wrote in the report covering the fiscal year ending Sept. 30.

Foxwoods restructured its debt in 2013 after defaulting in 2009 on a $2.3-billion debt agreement. In August, the Mashantucket Pequot tribe, which owns the casino, said it had defaulted on some covenants in the new debt agreement, which expires June 30.

During the past year, Foxwoods reported EBITDA of $147.4 million, down 28 percent from the previous fiscal year. Net revenues declined 7.7 percent to $960.1 million.

Revenues at both Foxwoods and the Mohegan Sun casino in Uncasville have declined sharply in recent years amid declines in local consumer spending amid a slow recovery from the recession and competition from new casinos in New York and Pennsylvania.

Mohegan Sun’s EBITDA fell 10.6 percent to $251.1 million in fiscal 2015. CEO Mitchell Etess told The Day that business was hurt by bad weather and poor performance on table games. Mohegan Sun also incurred corporate costs related to its failed bid for the eastern Massachusetts casino license which was awarded to Wynn Resorts.