The settlement would also block any new lawsuits against Travelers arising out of the insurance company's long relationship with Johns Manville Corp., once the world's largest producer of asbestos.

Travelers has been named in dozens of lawsuits claiming that it tried to hide the dangerous health effects of asbestos. Asbestos is a mineral that was commonly used until the mid-1970s in insulation and fireproofing material. Exposure can increase the risk of lung cancer, mesothelioma and other ailments, according to federal health agencies.

The company has argued that asbestos-related claims should be paid out of a trust created by Johns Manville in the 1980s and approved by a federal bankruptcy judge. Money for the fund came largely from insurers.

Travelers agreed to settle with several groups of plaintiffs provided that federal courts make clear that it would not have to face any new similar lawsuits.

The 2nd U.S Circuit Court of Appeals in New York overturned lower-court approval of the settlement, saying a bankruptcy judge lacks the authority to act so broadly. The justices, at arguments in March, will consider the question of the bankruptcy court's power.

The consolidated cases are The Travelers Indemnity Co. v. Bailey, 08-295, and Common Law Settlement Counsel v. Bailey, 08-307.