ROCKVILLE -- Citibank will make a major expansion into the Washington suburbs this month, but state legislators say the move may violate a 1985 state law designed to limit the New York financial giant's clout in Maryland.

Citibank (Maryland) N.A. is scheduled to complete the purchase of five Equitable Bank branches in Silver Spring, Gaithersburg, Rockville and Riverdale on Feb. 19. The New York-based bank's presence in Montgomery and Prince George's counties is currently limited to one branch in Bethesda.

The deal reportedly would add $50 million in Equitable deposits to the $228 million in deposits now held by the Citicorp subsidiary.

But state legislators said the acquisitions may violate a law that prohibits Citibank from acquiring Maryland banks or a "substantial" amount of their assets until the General Assembly relaxes restrictions on national interstate banking.

The change could occur in the current General Assembly session, but Citibank shouldn't make any moves until the law is amended, said delegates Brian Frosh (D-Montgomery) and James Rosapepe, (D-Prince George's). Both said they believe Citibank is trying to sidestep the restrictions by purchasing the Equitable branches.

Citibank gained limited access to the Maryland market in 1985 when the General Assembly authorized it to come to Maryland, providing it invested $25 million in the state, created 1,000 new jobs and did not acquire Maryland banks or a significant portion of their assets.

Under the agreement, Citibank could start up to 20 branches in two years, but it had to create new branches -- a measure designed to allow Maryland banks time to build their operations before facing competition from the powerful New York financial community, Rosapepe said.