Sinclair Broadcasting Group said it is considering seeking U.S. bankruptcy protection if it can't pay down its substantial debt that's coming due.

The Hunt Valley, Md., owner of television stations, which depends on automotive advertisers for revenue, said it may be obligated to pay $488.5 million of its outstanding debt within 18 months, the Baltimore Sun reported Tuesday. The company said it has $1.3 billion in total debt as of March 31.

"We do not have the cash necessary to meet our (debt) repurchase obligations," if note-holders exercise options in May and January 2011, the company said in a filing with the Securities and Exchange Commission.

If it can't restructure its debt or secure debt and equity financing, Sinclair said it may consider selling assets or restructuring through a voluntary Chapter 11 bankruptcy filing.