He often picked up phone calls from reporters during rest time at Preliminary Working Committee meetings in Beijing, or stopped in the hotel lobby to explain patiently the Central Government's policy. His other Hong Kong and mainland colleagues simply could not be reached.

At a farewell banquet he hosted for dozens of journalists on Wednesday, Mr Guo said: 'Looking back over the past few years, we have had some bad feelings towards each other.

'You have complained that I did not talk a lot. I've had some complaints as well. You guys always surrounded me and in some cases I almost fell on to the ground.

'It's time to put the old scores behind us with a toast . . . I hope you will not count the old scores in future,' he quipped.

Settling old scores with journalists proved a far easier task than drawing a balance sheet for his encounters with the British and Germans. Mr Guo was Chinese ambassador to the then West Germany before he was posted to head the Foreign Ministry's Hong Kong and Macau Affairs Office in 1988.

Pressed by journalists about his experience in dealing with the Germans and Britons, he appeared to think deeply, but just put it lightly: 'Those were very different times.' His aides say he might write some memoirs later, but not for a few years.

Posted to Bonn at the best of times for Sino-German relations, the career diplomat who can switch from German to French and English to Putonghua has won praise for his success in boosting bilateral ties.

But 'changes over the past four years have been drastic,' he lamented.

Arriving at Kai Tak with a broad smile in March 1990, Mr Guo then described his posting to Hong Kong as an 'interesting job.' He could hardly have anticipated that this was merely the beginning of one of the most memorable episodes in his diplomatic career.

Nine months after the June 4 massacre, Mr Guo was faced with the arduous task of getting the JLG machinery back to normal operation after three months of suspension. But the JLG's work simply could never be the same.

He was about to tackle the series of politically-explosive issues of the British nationality scheme, Bill of Rights and the second airport plan - the centrepieces of Britain's confidence-building plan to pick up the pieces after the June 4 shock.

The work of the JLG suffered another major blow following the arrival of Governor Chris Patten in 1992, or to put it more accurately, the announcement of his bold plan to widen democracy in the three-tier political structure - the last to be formed before the end of British rule.

Head of a team of about 30 staff in the JLG office which reports directly to the Foreign Ministry, Mr Guo has been faced with the task of looking for solutions to a long list of transitional problems, ranging from localisation and adaptation of laws, the sewage treatment strategy and the airport plan.

They have to study the piles of papers submitted by the Government, monitor the views of the community, hone their own expertise before formulating their ideas and then take a decision on what stance to take.

More often than not, however, Mr Guo's hands have been tied. The progress of the JLG work, or the lack of it, has often been dictated by the mood of relations between the two countries at a more senior level.

Insiders close to the diplomatic talks admit that their discussions, even on purely technical matters, have inevitably suffered when political relationships turned sour.

Even if Mr Guo and his aides wanted to quicken the speed of their work the reality did not allow them to do that.

The delay over talks on the financing arrangements for Chek Lap Kok was a glaring example of how the political row has taken its toll on economic projects.

Privately, officials involved with the JLG talks admit they were often frustrated by the snail-like pace of their work.

Keeping a low-profile, Mr Guo knew only too well that excessive exchanges of words in the public did little to solve problems. They would only increase the political temperature, as many cadres from the Xinhua headquarters have done.

The seasoned diplomat has been able to draw a clear line over what he should talk about in public, bearing in mind that any inappropriate comments on the territory's internal matters would be seen as gross interference.

Small episodes showed that he has had a good grasp of local sentiments.

For instance, he avoided harsh words over the public reaction to the June 4 killings when asked last week about what he was most impressed with in the past four years.

'When I came here something had already occurred in 1989. Many Hong Kong people still did not understand the situation on the mainland. It is understandable that they might have all kinds of thoughts.' But even though Ambassador Guo might have shared the same air as the six million people of Hong Kong, his job remained the full implementation of central policy.

He said last week his biggest wish before his departure around November 9 would be the signing of the airport financing deal. All signs are now that his diplomatic career in Hong Kong will come to a cheerful end.