THE chief representative of Taiwan's Straits Exchange Foundation (SEF) yesterday said it would like to set up an office in Hong Kong before 1997 to provide services to Taiwan residents in the territory. Chiao Jen-ho, the SEF's vice-chairman and secretary general, said an office had been planned for a long time to cope with the increasing traffic between Hong Kong and Taiwan. He said the number of Taiwan visitors to Hong Kong had reached 1.77 million last year. Mr Chiao was talking in Hong Kong while on a stopover after a visit to France and Holland with his wife and another SEF official. An SEF office in Hong Kong, he said, is not expected to duplicate the work of other Taiwan government branches in the territory which come under the Foreign Ministry and Government Information Office. It was Mr Chiao's first visit to Hong Kong since he joined the foundation about a year ago. Although he passed through the territory early last February when he made a landmark visit to the mainland, he did not stay. Mr Chiao confirmed that the SEF has not been authorised to initiate discussions with the mainland on Hong Kong after 1997. He said it would need authorisation from the Mainland Affairs Council before such discussions could take place. Mr Chiao declined to comment on the negotiations between China Airlines in Taiwan and Cathy Pacific in Hong Kong. The air treaty between Taiwan and Hong Kong will expire in May 1995 and the two airlines have been trying to hammer out a new arrangement to apply until July 1, 1997. Mr Chiao is returning to Taipei today, according to the Central News Agency.