(Adds detail from regulatory filing)

NEW YORK, June 17 (Reuters) - A unit of insurer American International Group Inc (AIG.N: Quote, Profile, Research) will cease to offer certain mortgages, the company said on Tuesday.

Wilmington Finance Inc, a unit of AIG wholly owned American General Finance, will cease to offer mortgages through brokers effective immediately and cut 335 jobs by the end of the year, according to a statement.

Wilmington will honor existing loan commitments and maintain a reduced retail operation, it said.

The company, which has specialized in residential real estate loans, including subprime, that were then sold off to third parties, cited "extraordinary developments in the mortgage banking industry during the past year" for the moves, according to a separate regulatory filing. The company said it does not see the market improving any time soon.

The Evansville, Indiana-based company said it expects to take a pre-tax charge in the second quarter of about $27 million related to lease termination costs, fixed asset disposals, intangible impairments and one-time termination costs. (Reporting by Lilla Zuill; editing by Mark Porter and John Wallace)