Zhai Zhigang, a reserve for the Shenzhou V and VI missions, is poised to become China's first spacewalker, reports have said.

Three 42-year-old astronauts - Zhai Zhigang, Liu Boming and Jing Haipeng - have been selected to carry out the country's third manned space mission, which will last from Sept 25-28, according to China.com.cn.

Zhai is expected to conduct a 40-minute spacewalk between Sept 26 and Sept 27, with Liu as his substitute.

As part of the session, Zhai will retrieve an undisclosed amount of "solid lubrication material" placed beside the gate of the orbital module. Before he does that, Liu will help him put on a special spacesuit that weighs in at about 120 kg and is worth 100 million yuan ($14.6 million).

Zhai, a native of Heilongjiang province, will hold a private space-to-Earth conversation with his family during the mission, Astronaut Center of China (ACC) director Chen Shanguang said earlier during a briefing at the Jiuquan Satellite Launch Center in Gansu province.

The ranking of all six members of the crew has remained unchanged after successive physical and psychological tests by an expert panel that monitored, logged and reviewed their status around the clock, Chen said.

"That means the men we've selected are the most qualified for the task," he said.

All six members of the Shenzhou VII mission belong to China's first generation of 14 astronaut candidates, selected in 1998.

"All of them are at least 40 years old now and after this mission, we will arrange for some of the astronauts' retirement or work transfers," Chen said.

While there are no specific plans to find a female astronaut, Chen said the ACC is engaged in relevant "technical preparations".

Scientists have promised a record-high safety index of 0.997, which means that for every 1,000 missions, 997 astronauts will return safely.