CHINESE police, granted the power last week to interview suspects in Hong Kong, will only be able to do so under supervision and with the suspects' agreement. The Director of Criminal Investigations, Senior Assistant Commissioner Tsang Yam-pui, said most requests would be dealt with under the landmark cross-border law enforcement agreement. He envisaged mainland police wanting to talk in Hong Kong to people thought likely to be involved in cross-border crime. Expanding on talks held last week in Beijing between Police Commissioner Eddie Hui Ki-on and senior Chinese officials, Mr Tsang insisted investigations would only be conducted with the consent of the suspect. He rejected claims that negotiations had started on setting up a mainland police office in Hong Kong. It is believed formal approaches for visits and interviews will be monitored by the Interpol office. Mr Tsang will ultimately be responsible for approving these approaches. ''Interviews will be allowed to take place,'' Mr Tsang said. ''But they will have to be approved and supervised by Hong Kong officers. '' People in custody have clear rights to legal advice and they can either consent to or refuse an interview. ''The issue of visits by investigating officers is quite clear: if there is any criminal intelligence or information of value, they have agreed to inform us promptly. ''We have only reviewed existing arrangements. The system can be further enhanced. What we are talking about at the moment is an increase in joint seminars.'' Mr Tsang, however, ruled out any direct exchanges of officers, saying there were no plans to replace the programme transferring police between Hong Kong and Britain with a Chinese transfer programme. ''Any permanent postings will not be necessary at this stage,'' he said. Seminars will take place early next year exploring cross-border techniques on drugs, interdiction, smuggling and illegal firearms. There are plans for a greater intake of mainland officers to study policing methods in communication and personnel management. The Chinese envy the Hong Kong force's sophisticated enhanced command and control system, which monitors officers' development. In the next few months, Chinese police will be asked to participate in the territory's financial investigations course. Narcotics Bureau experts will give lectures to crime fighters from all over the world on latest methods of tracing the money trail. Mr Hui's inaugural visit to the mainland as police chief was widely heralded as a triumph. The highlight of the tour to Beijing was his meeting with the Director of the Hong Kong and Macau Affairs Office, Lu Ping. But whether Chinese police can conduct investigations at random in the territory remains unclear. Mr Hui will visit the Guangdong Public Security Bureau next month.