Hoffman Estates-based Sears Holdings Corp., the struggling retailer backed by hedge fund manager Eddie Lampert, rose the most in almost two months after lining up a $200 million letter of credit to help fund its money-losing operations.

The amount could be expanded to as much as $500 million with the consent of lenders, according to a statement Thursday. Affiliates of ESL Investments Inc. - a firm run by Lampert, who also serves as Sears's chief executive officer, is providing the promise of funding through Citigroup Inc.

The move signals that Lampert remains committed to bankrolling Sears, even as the department-store chain suffers from dwindling sales and billions in red ink. After acquiring the once-mighty retailer more than a decade ago, he has sold off assets and real estate in a bid to return the company to profitability. The hedge fund manager, who is also Sears's biggest investor, became CEO of the business almost four years ago.

The stock jumped as much as 8.7 percent to $8.89 in New York trading following Sears statement Thursday, marking the biggest intraday gain since Nov. 14. The shares had lost more than 60 percent of their value this year before the latest rally.

Despite the stock reaction, it's a troubling sign that Lampert himself seems to be the only one willing to lend to Sears, said Noel Hebert, an analyst at Bloomberg Intelligence.

"The only person lending here is Eddie," he said. This isn't a "normal course" of action.

Lampert's firm also is helping support Seritage Growth Properties, the real estate investment trust spun off from Sears in 2015. ESL will provide a $200 million unsecured line of credit, Seritage said this week.

Earlier this month, Sears reported another huge quarterly deficit -- $748 million -- bringing its total losses to $9.35 billion in the past eight years. The company needs to raise about $1.5 billion to make it through 2017 comfortably, according to Christina Boni, an analyst at Moody's Investors Service.

Thursday's announcement of a "letter of credit" stops short of providing an actual cash infusion, Hebert said. Rather, it provides a backstop to vendors.

It also raises concerns that Sears is seeking financing right after the holiday season, which is the most lucrative time of year for retailers, he said.

"They weren't able to generate a ton of cash out of it -- if any," he said.

Sears Chief Financial Officer Jason Hollar said in Thursday's statement that the company has numerous options for financing.

"We will take actions to adjust our capital structure, generate liquidity and manage our business to enable us to execute on our transformation while meeting all of our financial obligations," he said.