China has less than four years to go before the Olympics in Beijing

The city unveiled a timer by Tiananmen Square that will tick off the seconds, minutes, hours and days until the start of the Beijing games in August 2008.

"The clock will witness the realisation of China's century-long Olympic dream," an organising committee official said.

Correspondents say the Chinese government is attaching great national pride to its hosting of the Olympics.

Liu Qi, Beijing's Communist Party secretary, has described the country's duty to hold good games as "a heavy responsibility" and a "glorious historical duty".

China saw the Athens games as a good training ground for the 2008 Olympics, in which it hopes its athletes will do even better on home turf.