Chinese President Xi Jinping has urged further integration of air and space defence capabilities, in what experts described Tuesday as a response to the militarisation of space by rivals including the United States.

China says its ambitious space programme is peaceful, but such claims were first questioned in 2007 when the military used a ground-based missile to destroy one of its own satellites in orbit.

According to several specialist websites, China last May also tested part of a new anti-satellite ballistic missile.

Xi told the country's air force to "speed up airspace integration and sharpen their offensive and defensive capabilities", the official Xinhua news agency said late Monday in a report which did not elaborate on how this should be done.

The state-run China Daily newspaper on Tuesday quoted Wang Ya'nan, deputy editor-in-chief of Aerospace Knowledge magazine in Beijing, as saying the move was in response to the "need of the times".

"The United States has paid considerable attention and resources to the integration of capabilities in both air and space, and other powers have also moved progressively toward space militarisation," Wang was quoted as saying.

"Though China has stated that it sticks to the peaceful use of space, we must make sure that we have the ability to cope with others' operations in space."

The China Daily article said "the idea of combining air and space capability is not new to the Chinese air force".

But China's space programme has previously focused more on commerce and science rather than defence.

Beijing sees the programme as a symbol of its rising global stature and technological advancement, as well as of the Communist Party's success in reversing the fortunes of the once-impoverished nation.