Mr Wang, in an interview with the Chinese state newspaper China Daily, said Mr Chen's plan to write a new constitution by 2006, and - subject to a referendum - enact it by 2008, was a serious threat to cross-Strait stability.

"New tensions may arise and even a serious crisis in the cross-Straits situation, if Chen obstinately pursues his timetable," he said.

"We cannot completely rule out the possibility (of a military conflict) though it is not at all what we hope for." The parentheses were provided by the newspaper.

China regularly uses strong language to denounce Mr Chen, but it is less usual for senior officials to talk openly of the risks of conflict.

Analysts say the row over Taiwan's proposed constitutional changes is likely to heat up in coming months as Mr Chen moves forwards with his plans.

Mr Wang's comments are also significant because China hosts the Olympics in 2008, and analysts in Taiwan had assumed China would be reluctant to contemplate any military action before then.

Mr Wang went on to say that it was difficult to improve current cross-Strait relations unless President Chen embraced the "one-China" principle - that there is only one China, and Taiwan is part of it.

Both Taipei and Beijing have been conducting war games in the last two weeks, preparing for the eventuality of cross-Strait conflict.

President Chen took part in a submarine dive on Thursday, and China has staged a mock-invasion of the island.

RELATED INTERNET LINKS:
Chinese foreign ministry
Taiwan government
US report on China's military 2004
Taiwan Flashpoint
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