Nearly 10 years ago, the District government proposed building 139 units of federally subsidized housing for low- and moderate-income families on a vacant parcel in Southwest. Nearby homeowners went to court and won the unusual right to approve almost any project built on the land.

Today, the city is supporting a plan that calls for building a mammoth $210 million international cultural and trade center on the property, and community opposition so far appears milder.

The project, proposed by the influential Federal City Council, has gained quick support from a variety of federal and city officials, but city officials admit they have done little to determine how they will obtain consents from nearby property owners as required by a 1980 decision of U.S. District Judge Harold Greene.

Greene ruled that because the parcel is in an urban renewal area the city must obtain written approval "from all purchasers or the project area who may be substantially and adversely affected" by any proposed development.

But Green also ruled it is up to the city to determine who will be considered "affected" residents.

Kenneth Colburn, a District housing official, said, "There's no sense in determining who is affected by the plan" until other government agencies that have the authority to change it approve the new project.

Many community residents, including some who brought the court lawsuit, play down the importance of their right to approve the project, primarily because they say they like the trade center proposal.

The Federal City Council, a private organization of city business leaders, lawyers and some political leaders and a strong supporter of the original Southwest urban renewal program, has proposed construction of the international center that would house foreign chanceries, suites for international organizations and U.S. government offices.

The project, financed by bond sales, would be built on 17 acres in Southwest, including the controversial city-owned parcel that lies between Seventh and Ninth streets, G Street and the Southwest Freeway. The remaining land is owned by the federal government.

The 3.3 acres, designated as Parcel 76, became a community battleground in 1974 when the city proposed building a subsidized housing project there. Fifty residents of town houses across Seventh Street from the tract argued in a lawsuit that they had bought their homes in part because of an urban renewal plan that called for a church or school to be opposite their property, not subsidized housing.

Greene ruled city officials could not change the urban renewal plan for Parcel 76 without the near-by property owners' consent. The District appealed the decision but lost.

Today, some people who brought the suit, including their lawyer, Arthur H. Berndtson, support the international center and criticize those who oppose it.

"They [would] be cutting off their noses if they try to stop this project," Berndtson said. "This project would be in the best interests of the District of Columbia. It would be in the best interests of the people in Southwest. I think it would be a wonderful thing for the neighborhood."

More than half the residents in the Town Square condominiums, directly across Seventh Street from Parcel 76, supported the proposed development in a recent informal poll sponsored by the building's governing board.

Resident Tamara Liller, who conducted the survey of 103 residents in the 282-unit building, said 58 percent favored the trade center, 27 percent opposed it and 14 percent had no opinion.

Several condominium owners said in recent interviews they supported the center because they believed it would increase their property values unlike the defeated subsidized housing project that they believed would lower the values.

The Federal City Council, armed with $253,000 in architectural drawings, has been courting Southwest residents. "We have been doing everything possible to minimize problems for the people in that immediate area and to make the project as agreeable to them as possible," said Kenneth Sparks, the council's vice president.

He said the group has changed its design plans three times to quell objections that the project would obstruct views in the high-rise condominiums at 700 Seventh St. SW.

But some opposition to the project is developing because of its size and the traffic it would generate.

"We're talking about something that is twice the size of the convention center," said Gottlieb Simon, executive director of Advisory Neighborhood Commission 2D. "Many people just don't want that kind of imposing, dominating presence, a kind of behemoth in the middle of their neighborhood," he said.

Brian Moore, chairman of the Near Southwest Southeast Comprehensive Planning Review Panel, a coalition of Southwest church organizations, residents and businessmen, said his group opposes the proposed complex because it would draw tourist traffic and change the residential character of the neighborhood.

James Foley, a George Washington University professor who has lived in a Sixth Street town house since 1976 and helped finance the lawsuit, said the proposed trade center "has some nice features." But he also expressed concern about its size, the increased traffic it would generate and the playing fields at Jefferson Junior High School that would be lost because of the development.

Like many Southwest residents, Foley said it will be difficult to defeat the proposed urban renewal plan change.

"There's room for more litigation, and some people might object," Foley said. "But this time we're only talking about a small bunch of opponents . And it would take more than a small bunch of people to make an impact on a project like this." CAPTION: Map, no caption. By BRAD WYE for The Washington Post; Picture, The parking lot at Seventh and G streets SW would become a $210 million international cultural and trade center under a proposal by the Federal City Council. By Vanessa Barnes Hillian--The Washington Post