Congress was urged yesterday to combat the January decline in housing starts by increasing authorization for federally subsidized dwellings from 300,000 to a minumum of 400,000 units" during the fiscal year beginning in October.

The National Housing Conference, a coalition of professionals interested in the building, financing and management of housing, called upon federal lawmakers to move now to provide supplemental appropriations and to take other actions to increase the level of subsidized units from the 300,000 targeted in the Carter budget.

Leon N. Weiner, a Wilmington developer and president of the NHC, said at a press conference yesterday that Congress also should set a target of 2.5 million nousing starts annually "because the market and need are there, beyond any question." In 1977 and 1978, housing starts averaged 2 million, plus nearly 300,000 mobile/ manufactured homes. manufactured homes.

Weiner insisted that production of 2.5 million new homes a year is "eminently possible." and added that an accelerated replacement of substandard housing could "justify a level of 3 million starts."

However, starts fell to an annual level of 1.6 million in January, and Weiner forecast a total this year of only 1.5 million, with a decline to an annual level of 1.3 million by the end of this year. That is in the lower part of the range of most housing industry forecasts. February housing starts are expected to be below the January level because of the bad weather throughout much of the nation.

In an address to more than 300 NHC members at the Capital Hilton, Rep. S. William Green (R-N.Y.) charged that housing policy "is being held hostage to inflation by the administration" making massive cuts in national housing programs. Earlier, Sen. Harrison Williams (D-N.J.) said that current housing programs "have been drafted to serve as cannon fodder in the fight against inflation."

However, HUD Secretary Patricia Harris told NHC Monday that "President Carter has not made housing the first and greatest sufferer in efforts to curb inflation."