A Maryland savings and loan merger was completed officially this week, but two Virginia savings institutions called off their proposed combination.

John Hanson Savings & Loan, based in Prince George's County, said it finished its previously announced acquisition of Metropolis Building Association of Baltimore. The combined S&L has assets of $230 million and 17 offices in the Washington and Baltimore markets, making it one of the largest savings institutions in the state.

In an unrelated development, First Financial of Virginia Corp. in McLean and Virginia First S&L of Petersburg, in southern Virginia, canceled an earlier plan to merge. First Financial is the parent company of Washington-Lee S&L and the proposed combination would have created one of the largest S&Ls in the state.

First Financial/Washington-Lee President Richard Lawton and Virginia First President William Patton blamed the demise of their accord on "current economic conditions which have adversely affected the S&L industry." "But they held out the possibility of resuming merger talks at a future date.

"The decision does not reflect on the financial strength or integrity of either eompany but rather allows time for both companies to deal with the current issues facing them," the officials stated.

John Hanson Chairman Charles Dukes Jr. said his firm's acquisition of the smaller Baltimore S&L is "another significant step in the organization, growth and expansion which started in 1970 and will enable [the S&L] to compete more favorably in the marketplace . . . at both ends of the I-95 corridor."

John Hanson is the first D.C.-area S&L to have a significant position in the Baltimore market although Baltimore-based S&Ls and Annapolis Federal have been active in the Washington suburbs in recent years.

Washington-Lee has 21 offices in Northern Virginia with assets of $388 million.

Still in the works is the largest S&L merger in Virginia -- a combination of Arlington-Fairfax S&L of Falls Church with First Federal S&L of Arlington, which is based in Fairfax City. The combined institution, with assets of nearly $775 million, would be called Atlantic Federal S&L and be based in Fairfax City. The Arlington-Federal combination with First of Arlington is waiting for approval by federal S&L regulators.