The rapidly increasing cost of oil and the resulting spike in the price of jet fuel have presented a challenge in the sale of Sun Country Airlines.

Court documents filed last week indicated that the Mendota Heights-based airline is close to a sale, but the potential buyer and the purchase price haven't been disclosed.

According to the Star Tribune, attorney Daryle Uphoff-who is representing Doug Kelley, the trustee for the Tom Petters bankruptcy estate-on Tuesday told U.S. Bankruptcy Judge Gregory Kishel that “events in the Middle East have not created a favorable environment for Sun Country.”

Uphoff appeared before Kishel to request that the minimum purchase priceacceptable to Kelley be kept under seal in order to discourageexcessively low bids. Kishel granted the request.

When contacted by Twin Cities Business via e-mail, Uphoff would not confirm any information about Sun Country's possible sale, referring questions to Sun Country's in-house general counsel, John Fredericksen, who didn't immediately respond to a forwarded request for information.

But Uphoff indicated in court documents and Tuesday's court proceedings that negotiations with a single potential buyer are underway.

“These have been intense negotiations and those continue,” Uphoff reportedly told Kishel. “Whether they lead to a final agreement, we're hopeful.”

Sun Country filed for Chaper 11 protection in October 2008 just three days after Tom Petters-the airline's majority stockholder-was arrested on charges related to investment fraud. Petters is now serving a 50-year sentence for running a Ponzi scheme that defrauded investors of an estimated $3.65 billion.

Petters Aviation, LLC, a unit of Minnetonka-based Petters Group Worldwide, along with Minneapolis-based Whitebox Advisors, acquired Sun Country in 2006. In 2007, Petters Aviation purchased Whitebox's share of the company. Petters Aviation is currently the airline's main shareholder.

Sun Country-which officially emerged from bankruptcy late last month-has been looking for a buyer for at least a year. In a reorganization plan filed in April 2010, which outlined the airline's plans to exit bankruptcy, the company said that it believes that “the indications of interest confirm a valuation in the range of $10 million to $30 million.”