The Long March 5B rocket, that carried a Chinese space station module, has dropped into low Earth orbit and now risks crashing back down.

Media reports say that the United States (US) Space Command is tracking debris from the Long March 5B, which last week launched the main module of China’s first permanent space station into orbit.

The roughly 30-metre (100ft) long stage would be among the biggest space debris to fall to Earth.

The US defence department expects it to fall to Earth on Saturday though where it will hit “cannot be pinpointed until within hours of its re-entry”, the Pentagon said.

The White House press secretary, Jen Psaki, said on Wednesday: “The United States is committed to addressing the risks of growing congestion due to space debris and growing activity in space and we want to work with the international community to promote leadership and responsible space behaviours.”