HONG KONG, SEPT. 23 -- Britain has announced a breakthrough with Vietnam on the nonvoluntary repatriation of boat people from Hong Kong, saying Hanoi will now accept the return of those who have not volunteered as long as no force is used to remove them.

The announcement came after two days of talks in Hanoi late last week among representatives of the British, Hong Kong and Vietnamese governments and officials from the United Nations High Commissioner for Refugees (UNHCR).

A joint statement issued after the talks avoided the term "forcible repatriation," saying the parties had "agreed the modalities of repatriating those who, while not volunteering to return, are nevertheless not opposed to going back." The statement said the UNHCR would play an "active role fully compatible with its humanitarian mandate."

Officials said the careful wording of the statement was aimed at satisfying both the United States and Vietnam.

About 54,000 Vietnamese boat people are languishing in squalid and prison-like conditions in Hong Kong's many camps and detention centers. Fewer than 13,000 have been judged "genuine" refugees who fear political persecution at home and are thus entitled to be resettled in a third country.

Washington's opposition to mandatory repatriation put a halt to a British program of forcibly returning to Vietnam those boat people not judged to be genuine refugees. Hong Kong authorities forcibly sent 51 boat people back to Vietnam last December, but the program was shelved because of international condemnation led by Washington.

The officials said Vietnam was eager not to jeopardize its chances of improving relations with Washington, which maintains sanctions against Hanoi. The meeting in Hanoi was called by Vietnam, whose economy is suffering because of aid cuts by the Soviet Union and former East Bloc.

Analysts said Hanoi hoped that the policy change would lead to a European Community aid package and improved ties with its Southeast Asian neighbors.

A U.S. official in Hong Kong said Washington had no objection to the new program, as it fit "within the parameters of what the United States has agreed to." The official added, "We are still opposed to the use of force."