The government said last year that the Shenzhou 7 craft would launch sometime in 2007, though no date was given. It said the mission would be manned by three astronauts and include a spacewalk - a first for China's space program.

"There is nothing wrong. We just need more time to prepare for the mission,'' Huang Chunping, chief consultant for China's manned launching vehicle system, was quoted as saying by the official Xinhua News Agency.

China launched its first manned space mission in 2003, making it the third country to send a human into orbit on its own, after Russia and the United States.

A second, longer mission carrying two astronauts was completed last year.

• Shenzhou 6: Complete Coverage of China's Second Manned Spaceflight
• Making History: China's First Human Spaceflight