Chinese astronauts practice manoeuvring in a water tank designed to simulate the low-gravity environment of space.

JIUQUAN, Gansu Province, Sept. 6 (Xinhua) -- China's manned spacecraft Shenzhou-7 will be launched at an appropriate time between Sept. 25 and 30 from the Jiuquan Satellite Launch Center in northwestern Gansu Province, a spokesman said here on Saturday.

The crew had conducted drills and their controlling over the system was "skilled" and they were in "good" physical and mental state, said the spokesman.

The information was revealed at a meeting held by the headquarters of the mission, which will accomplish the first spacewalk by Chinese astronauts.

The spokesman said propellant will be instilled into the spacecraft on Sunday. After that the spacecraft will be joint with the rocket and they will be transferred into their launch place for the final check.

"All the major systems involved in the launching are now in the final preparation. The main tests for the spacecraft, the Long-March II-F rocket, suits for the space walk and a satellite accompanying the fly have also been finished," said the spokesman.

In addition, the ground control system is fully prepared, including the launch site, the landing site, and the communication for observation and control.

When Shenzhou-7 enters its orbit, one of the three taikonauts will conduct a space walk, said Zhao Changxi, a seniorscientist with the project, earlier.

According to Zhao, cameras would be mounted outside and inside of the ship for live broadcasting of the space walk.

While the last mission of Shenzhou-6, with a crew of two, was aimed at multiple days of manned flight, this time the task might be more stringent as one of its main goals is the space walk, he said.

Earlier reports said a crew of six astronauts had been chosen for the mission, with three manning the spacecraft and three substitutes.

On April 12, China launched a new space tracking ship to serve the Shenzhou-7 spacewalk mission.

The new space tracking ship is the sister ship of the Yuanwang-5, which was put into use a year ago. The two vessels will play a key role in the Shenzhou-7 mission.

China successfully put two manned spacecraft into orbit in 2003and 2005 respectively, becoming the third country to send an astronaut into space after the United States and the former Soviet Union (now Russia).