Mayoral candidate David A. Clarke, chairman of the D.C. Council, said yesterday that Mayor Marion Barry should refrain from signing any leases or other commitments that would extend beyond his last seven months in office.

"Now that the mayor is clearly not going to be mayor, he should not be signing commitments for the city that are longtime and binding," Clarke said.

He made his remarks after a D.C. Council hearing at which Barry administration officials were questioned about proposed leases.

The administration has agreed to a 20-year lease, worth $216 million, to obtain temporary offices for the mayor and council while the District Building is under renovation from 1991 to 1994. The development group is led by Richard A. Bennett Jr., a major Barry contributor.

Barry has made a separate proposal to lease the site of the Department of Employment Services building at 500 C St. NW. The building would be razed for a new one, and the developer would construct a building elsewhere for Employment Services and other offices.

Council members John Ray (D-At Large) and John A. Wilson (D-Ward 2) have countered that proposal with one that would require the District to build a new District Building on the Employment Services site.

A third proposal is being negotiated by the Barry administration and Jeffrey N. Cohen, a longtime friend of the mayor's who hopes to build an office building for the city at 11th and U streets NW.

Cohen's proposal differs because the city would be able to buy the building for $1 after the 20-year lease. The lease payments in the 20 years would total about $150 million.

Council member Betty Ann Kane (D-At Large), who called the hearing, said the leases need to be considered in a coordinated manner.

She said that the District should try to own buildings, not lease; that it should consolidate offices in two locations, the courts area near the Employment Services building and the Shaw area near the Reeves Municipal Center and Cohen's proposed building; and that it should plan for a reduced work force, not an expanded one.

Raymond A. Lambert, Department of Administrative Services director, told Kane he would submit a plan for office space by Sept. 1.