SHANGHAI, Jan 15 - China plans to land the first probe ever on the dark side of the moon in 2018, marking another milestone in its ambitious space programme, the official Xinhua news agency reported.

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 centre, as saying late on Thursday.

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

Advancing China's space programme 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 programme is for peaceful purposes.

However, the U.S. Defense Department has highlighted China's increasing space capabilities, saying it was pursuing activities aimed at preventing its adversaries from using space-based assets during a crisis.

In March, the Chinese government said it would open up its lunar exploration programme to companies rather than simply relying on the state-owned sector as before, hoping to boost technological breakthroughs.

Xinhua said China sent "a letter of intent of cooperation" on its latest mission to foreign countries in early 2015. It was not clear if any had signed up.