A coalition of unions and human rights groups filed suit Thursday in federal court here to force the Bush administration to review trade preferences for countries allegedly violating workers' rights.

Among the targets of the requested reviews are El Salvador, Guatemala and the Philippines, countries that are receiving U.S. duty-free benefits despite alleged workers' rights violations.U.S. unions and others are urging that those benefits be suspended.

Separately, Sen. Jesse Helms, R-N.C., is expected to introduce legislation next month that would impose sanctions on any imports from China involving forced or convict labor.

The bill would ban such imports totally, unless the president ruled otherwise for national security reasons, and would authorize U.S. firms to file treble-damage lawsuits for injury from those imports.

Joint U.S.-Chinese business ventures involving convict or forced labor would be prohibited.

The bill, an aide said, is likely to be co-sponsored by other senators. It will be introduced at a time when many in Congress believe that the administration has been "too soft" in its response to China's recent political crackdown.

On requests by Sen. Helms, the U.S. Treasury, Labor and Agriculture departments and the General Accounting Office are examining whether there is any evidence of U.S.-Chinese joint ventures or imports from China involving ''slave" labor.

In a letter this week to Agriculture Secretary Clayton Yeutter, Sen. Helms suggested that some "slave labor" agricultural exports are entering the United States.

He expressed "particular concern" that U.S. business, in joint ventures with the Chinese, may be "unwittingly using inputs from slave labor farms." He cited two such farms near Beijing that produce "a wide variety of vegetables, fruit and even cut flowers."

In 1984, a Helms aide noted, the U.S. International Trade Commission quoted reports from China citing the Ministry of Justice as operating coal mines and machine, chemical and textile factories.

In the lawsuit filed Thursday to force the Bush administration to review workers' rights practices in developing nations, the International Labor Rights Education and Research Fund charged that the administration has failed to carry out U.S. trade law.

Ray Marshall, the fund's president and a former U.S. labor secretary, said the law bases duty-free benefits partly on respect for workers' rights in the recipient countries.

But, he and others noted, the U.S. Trade Representative has refused even to review anti-labor violence in El Salvador and some other nations.