SAN FRANCISCO -- The San Francisco Chronicle newspaper plans to cut about a quarter of its newsroom staff.

Management told union leaders Thursday that it plans to eliminate 80 union and 20 management positions, out of a newsroom staff of about 400.

Managers told the union the cuts were necessary because of the paper's continuing financial losses, Michael Cabanatuan, president of the Northern California Media Workers Guild, said in a prepared statement. The Chronicle published a brief news story about the staff reduction Friday.

The guild has proposed a plan to achieve the target number of job reductions through voluntary buyouts and retirement incentives, which management is considering, Cabanatuan said.

In an e-mail distributed by the union to its members, the guild said management could make "involuntary reductions" if 80 cuts could not be made through the buyout and retirement incentives within 30 days.

Two spokesmen for the newspaper did not return phone calls seeking comment Friday.

Chronicle Publisher Frank Vega was quoted in the newspaper's story saying: "Representatives from the Chronicle did meet (Thursday) with guild representatives to initiate discussions on early retirement and buyout programs involving a significant number of people. We are not prepared to discuss specifics because it was just a preliminary conversation."