China is expected to launch a new crewed mission into space this week, as Beijing takes steady steps towards its goal of putting astronauts on the moon.

The Shenzhou-20 mission will blast off from the Jiuquan Satellite Launch Center in northwestern China, carrying three astronauts to the country's self-built Tiangong space station.

The space agency said last week that the Shenzhou spaceship and its Long March-2F carrier rocket were transferred to a launch site at the remote desert base and would launch "at an appropriate time in the near future".

Photographs published by Xinhua News Agency showed the sleek white rocket perched on a blue pedestal.

"At present, the launch site facilities and equipment are in good condition. The functional inspections and joint tests will be carried out as planned," the China Manned Space Agency (CMSA) said.

Zhou Wenxing, a staff member at the country's astronaut training centre, said the crew was "in good condition, precise in operation, and smooth in coordination", CCTV reported.

The previous crewed mission, Shenzhou-19, launched last October and will reach its planned end date on April 29.

It is headed by Cai Xuzhe, a 48-year-old former air force pilot who served a previous stint aboard the Tiangong space station as part of the Shenzhou-14 mission in 2022.

Also among the crew is Wang Haoze, 35, who is China's only female spaceflight engineer and the third Chinese woman to take part in a crewed mission.

Song Lingdong, 34, completes the trio.

The Shenzhou-19 team has been carrying out tests to see how extreme radiation, gravity, temperature and other conditions affect "bricks" made from components imitating lunar soil, according to reports at the time of the launch.

China's space programme was the third to put humans in orbit and has also landed robotic rovers on Mars and the moon.

The Tiangong space station is staffed by teams of three astronauts that are rotated every six months.

Beijing says it is on track to send a crewed mission to the moon by 2030.

In 2019, it landed its Chang'e-4 probe on the far side of the moon - the first spacecraft ever to do so. In 2021, it landed a small robot on Mars.

Tiangong, whose core module, Tianhe, launched in 2021, is planned to be used for about 10 years. (AFP)