China's Olympics chief has told officials to brace for the "decisive stage" of preparations for the 2008 Beijing Games and warned that the country is not at gold-winning standards in many sports.

"Battle preparations for the 2008 Olympic Games are in a grave state," the President of the Chinese Olympic Committee Liu Peng told sports administrators, according to the official Xinhua news agency late on Thursday.

Reaching for ancient Chinese military metaphors, Liu told officials to underplay the country's hopes for success in the showpiece sporting event.

"To the outside, we must display humble troops and keep a low profile, but inwardly we must plant grand ambitions to scale great heights, and there can be absolutely no slackening."

Chinese sports officials have continually played down hopes of toppling the United States from the top of the medals table in 2008.

Judging from China's performance at the recent Asian Games in Doha, Liu said, the country had reached "advanced world levels" in some sports but still lagged in others.

"In a considerable number of events, we lack competitiveness to win gold in the Olympics," he said, noting that the U.S., Russia, Germany and Australia were preparing to shoulder past China in many events.

In major world competitions in 2005 and 2006, U.S. and Russian athletes won many more gold medals than China, he said.

"In overall strength in world athletics, we're still in the second league."

Liu, also executive president of the Beijing Organising Committee for the Olympic Games (BOCOG), said China's athletes had not improved quickly enough in track events and swimming.

The Beijing Olympics begin on August 8, 2008.