China is preparing to send its top official on Hong Kong affairs to this crown colony amid increasing warnings from Peking over the development of a democratic form of government here during the transition period before the territory reverts to Chinese rule.

Only 11 days after China upset Hong Kong's political calm by criticizing the territory's electoral reforms, news of the visit by the mainland's top Hong Kong affairs official, Ji Pengfei, has heightened uncertainty.

Ji will be the highest ranking Chinese Communist to make a public visit to the British colony since the founding of the People's Republic of China in 1949. The specific date of his visit has not been released.

The 76-year-old former foreign minister is a member of China's State Council and the director of the council's Hong Kong and Macau affairs office. Ji was an important participant during the two years of negotiations about Hong Kong's future after 1997, when sovereignty over the territory will revert from London to Peking.

Ji's visit has been under consideration for some time, according to reliable sources, and will come at a time of sharply increased tension between the two governments about the degree of autonomy Hong Kong will have after 1997.

On Nov. 21, China's top official based in Hong Kong, New China News Agency Director Xu Jiatun disrupted political calm in the British colony with an accusation that the British had "deviated" from the Sino-British agreement signed only last December by the British and Chinese governments.

By "deviation," Xu appeared to be referring to the addition by the Hong Kong government in September of some indirectly elected seats to the traditionally appointed membership of the local legislature.

On Friday, Peking appeared to be playing down Xu's comments, when Ke Zaishuo, chief Chinese delegate to the Sino-British liaison group overseeing the transition period, said he saw no evidence of British deviation from the terms of the 1984 joint declaration.

Ke's attempt to mollify Hong Kong public opinion did not impress advocates of political reform in Hong Kong. This week's issue of the Hong Kong left-wing publication Outlook carried hints from Hong Kong affairs expert Ji to the effect that the Peking government would intervene in Hong Kong's affairs if serious changes affecting the 1997 period occurred during the transition.

Diplomats have said that they interpreted Xu's attack as an attempt to preempt the development of local democracy before Peking has a chance to draft its own political system for the territory.

One source close to the Hong Kong government said that China would lose credibility if it tried to affect public opinion directly, "but they can try to shoot it down through the British."

They also read Xu's threats as a "warning shot" only five days before the liaison's group's second session in Peking, which ended yesterday.

During the talks, Chinese officials again raised the question of whether Britain had broken the spirit of the agreement. The atmosphere during that part of the discussion was described as "very tense."