China has launched a new round of work focused on lunar exploration, coming about two years after it made the first "soft landing" on the moon since 1976 with the Chang'e-3 craft and its Jade Rabbit rover.

Previous spacecraft have seen the far side of the moon, that is never visible from earth, but none has landed on it.

A new probe, the Chang'e-4, is similar to the Chang'e-3 but can carry a bigger payload, Xinhua quoted Liu Jizhong, head of the science, technology and defense industry administration's lunar exploration center, as saying late on Thursday.

The craft will study geological conditions on the far side of the moon, Liu said.

Advancing China's space program has been a priority of leaders, with President Xi Jinping calling for China to establish itself as a space power.

China insists that its space program is for peaceful purposes.