Twelve housing, local government and urban affairs groups have told Sen. Richard G. Lugar (R-Ind.), chairman of the Senate Banking subcommittee on housing, that they will not support his new housing aid plan unless he combines it with assistance for low income families.

A spokesman for Lugar, the top congressional Republican on housing matters, said the senator does not believe the two types of legislation should be combined because debate over low-income housing would weigh down the homebuying-subsidy plan, which is being offered largely as a job creation program.

Homebuilding industry officials and Democrats on the subcommittee reportedly were pleasantly surprised when Lugar introduced legislation to subsidize deeply mortgage interest rates for buyers of new homes, in an effort both to boost the industry and create jobs.

This had been the first support from a key congressional Republican for large federal subsidies to aid housing. Democrats on the House housing panel saw Lugar's sponsorship of the subsidies as a basis for compromise with their more ambitious and comprehensive plan for both homeownership aid for moderate income persons and assistance for low income families, a top staff aide said.

But the 12 housing and urban groups told Lugar in a letter Friday that it would be "unconscionable" to help middle-income homebuyers without aiding the poor.

Signing the letter were the U.S. Conference of Mayors, National Association of Counties, National Urban League, National League of Cities, National Urban Coalition, Council for Rural Housing and Development, National Leased Housing Association, National Housing Conference, National Low-Income Housing Coalition, National Association of Housing and Redevelopment Officials, National Housing Law Project and Interreligious Coalition for Housing.

"While we commend your initiative in introducing home-ownership legislation, the undersigned groups cannot support any such measure unless it is part of a comprehensive housing bill directed toward assuring that all Americans have a decent place to live," the letter states. "We hope you agree that aiding middle income homebuyers and the homebuilding industry without aiding the needy would be unconscionable."

Lugar had expected some supporters of the House Democrats' plan to try to link the ideas, said staff aide Mark Helmke. He added he would find it "hard to believe" that groups such as the League of Cities and Conference of Mayors ultimately would withhold support for a jobs plan if that were all it was possible to get this year.