ALBANY — New York’s top insurance regulator has directed insurers to detail payouts and reserves for claims in the 2001 World Trade Center attacks in an effort to prompt settlement of the decade-old federal case.

Benjamin Lawsky, superintendent of the Department of Financial Services, says in a letter that ongoing claims against the two airlines and security companies, following the terrorist attack on the twin towers in Manhattan, has slowed redevelopment and “undermined public confidence in the insurance industry.”

Developer Larry Silverstein has complained to the department about gridlock in settlement negotiations.

Federal law limited the insurers’ liability and created a special fund that paid victim claims.

Remaining insurer liability is estimated at about $2 billion.

Lawsky also seeks the insurers’ investment return rates since 2002 and their itemized bailout benefits.