''Everyone seemed very impressed with his performance,'' one delegate said.

All this was rather strange because even though Mr Zhu is an internationally recognised politician, technically he should not have been at the conference at all.

It was Mr Zhu's immediate boss, Mr Li Peng, who was to have represented the Chinese Government at the Interaction Council but, as has been apparent for the past three weeks, Mr Li was indisposed.

Not that anyone seemed to mind. In fact, it was generally agreed Mr Zhu's presence was the most natural thing in the world and hardly anybody commented on Mr Li's absence.

The ease with which Mr Zhu has slipped into his boss's shoes had not gone unnoticed in Beijing either.

''The transfer of power has been remarkably smooth,'' a Western diplomat said. ''Mr Zhu appears completely at home in his new role and, what's more, he seems to be enjoying every minute of it.'' However, it is not only the executive vice-premier who has been gaining at Mr Li's expense. Communist Party General Secretary and State President Mr Jiang Zemin has also been muscling in on the prime minister's turf.

Since his elevation to power in June 1989, Mr Jiang has largely avoided questions on the economy, that has always been the jealously guarded preserve of the prime minister.

Mr Jiang had been happy confining his attention to meeting foreign guests and giving party officials ideological pep talks from time to time, but he is becoming increasingly involved in the management of the economy.

The president tried his hand at macro-economic theory on Wednesday when he attended an international conference on the role of planning in the market economy.

He also gave the key note address to a government conference on the economic development of eastern China in which he called for the acceleration of reforms in the banking and financial sectors.

Mr Jiang's understanding of economics may still be rudimentary but he seems determined to exercise his authority nevertheless and one analyst said: ''You have to give him 10 out of 10 for effort.'' If Mr Li remains out of action for much longer, observers say he will be in danger of being squeezed out of the job altogether, or of being ''caught in the middle of a Shanghai sandwich'', as one diplomat put it.

He said people were starting to question his essentiality since everything seemed to be operating smoothly without him.

ust about everyone in the highest echelons of government except Mr Li seems to have a clearly defined role in the running of the country.

Government officials have publicly stated that it is Mr Zhu who is in charge of the day-to-day work of the State Council, China's cabinet, while the other three vice-premiers, Mr Qian Qichen, Mr Li Lanqing and Mr Zou Jiahua, supervise foreign policy, trade and economic policy, and economic and social planning respectively.

Mr LiPeng, it is said, is responsible for ''overall work'', a term suitably vague as to mean nothing at all.

Of course, it would be foolish to underestimate Mr Li's influence in the administration and his absence has given rise to some ripples on the otherwise smooth surface of government.

Die-hard leftist, Mr Song Ping, for example, felt it necessary to emerge from retirement and pound on a conference meeting table in a bid to reinforce the need for more political and ideological education.

However, after some appearances on the evening news, Mr Song has retreated back to his retirement home and the government has carried on as before.

The prolonged absence of Mr Li and the lack of any major dislocation as a result of it has prompted suggestions that the prime minister has developed a political rather than physiological illness.

One theory is that Mr Li is undergoing some forced rest and recuperation in the resort town of Suzhou, near Shanghai.

Mr Li, the theory goes, is being confined to a villa in the canal-lined town with a few armed guards for company.

The theory which comes from a now retired senior government official in Shanghai, states that, in the convoluted way of Chinese politics, it would have been too awkward for Mr Li to retire after the National People's Congress. The government would have had to explain why he was not re-elected and what mistakes he had made.

By having Mr Li fall ill, the government did not have to explain anything. ''Illness is illness,'' the official said.