VIETNAM says its policy on accepting back boat people has been misunderstood. It denied that its delegations to Hong Kong's camps had refused clearance to anyone volunteering for repatriation. The Hong Kong Government has been locked in negotiations with Vietnam through the British Embassy in Hanoi and envoys from Vietnam, but has been unable to overcome the refusal by Vietnam to clear some people for repatriation. There have been instances of people volunteering for repatriation as many as eight times in two years. Such cases are classified by the United Nations High Commissioner for Refugees (UNHCR) as ''pending''. The Vietnamese Vice-Consul in Hong Kong, Nguyen Than Thuy, said his Government regretted the suggestion that Vietnam had refused to accept back people wanting to return. ''It is a misunderstanding,'' Mr Nguyen said. The UNHCR acting chief-of-mission in Hong Kong, Aziz Ahamed, said that to state that Vietnam had refused to take people back was incorrect, but there were people who had not been cleared for return and had been classified as pending. Mr Ahamed denied semantics were being used to explain the situation and said he was confident all volunteers for repatriation would be cleared. ''We have been assured by Vietnam that they would look into the cases of people who have been labelled pending,'' Mr Ahamed said. Refugee lawyers, camp workers and UNHCR staff have reported a growing trend by Vietnamese delegations to the camps to refuse clearance for people seeking to volunteer for repatriation. It is understood that minority groups such as those who are ethnic Khmer, Taiwanese, or Chinese are among those who have been unable to return to Vietnam. It has been explained to Vietnamese officials that the Hong Kong Government faced a court challenge over its detention of ethnic Khmers who were given refugee status many years ago when they fled Cambodia for Vietnam. These people are now being held in Hong Kong camps and lawyers are preparing a case to challenge the legality of their detention. A top Vietnam foreign affairs official, Bui Hong Phuc, met the UNHCR and the Hong Kong Government last month to discuss the issue of not accepting back some voluntary repatriation applicants. The UNHCR asked Vietnam to consider the cases in a humanitarian and sympathetic spirit. A government spokesman said yesterday that it was not standard practice to release information on inter-governmental discussions of this nature. ''The repatriation of the Vietnamese migrants remaining in Hong Kong is a complex issue which involves constant dialogue with the Vietnamese authorities on a range of issues, including discussions on individual cases whose clearance for return is delayed for one reason or another,'' the spokesman said. About 24,000 Vietnamese asylum-seekers remain in the territory and must be cleared from the camps by the end of next year according to an international decree. Refugee Concern chairman Pam Baker said she had many clients who had been rejected for repatriation. She said one man, Thoong A Sang, had been screened out and had tried to volunteer for repatriation eight times. Mrs Baker said Mr Thoong was single and had no family in Vietnam. His mother had remarried when he was young and was subsequently sponsored to go to the United States by her stepsons. ''This poor man was actually told by the Hanoi delegation here that he should join his mother in the US, which, of course, is impossible because he has no refugee status. ''This is completely a game of semantics in saying people have not been refused, they have just not been cleared for return,'' she said.