China took a further step on Tuesday toward ending its dependence on U.S. satellites to provide navigation and positioning services with the start of trial operations of its homegrown Beidou system.

China started a drive to end its reliance on the U.S. global positioning system in 2000, when it sent an experimental pair of positioning satellites into orbit.

Ran Chengqi, spokesman for the new system, told reporters that Beidou, or Big Dipper, would cover most parts of the Asia Pacific by next year and then the world by 2020.

China has already launched 10 satellites to support Beidou and would launch another six next year, he said.

State media have said the system will eventually comprise 35 satellites, which will be used for a variety of sectors including fisheries, meteorology and telecommunications.

China has ambitious plans for space, including a space station and a manned trip to the moon.

While China has vowed never to militarize space, experts say it is ramping up the military use of space with new satellites.

The successful missile kill of an old satellite in early 2007 represented a new level of ability for the Chinese military, and last year China successfully tested emerging technology aimed at destroying missiles in mid-air.

(Reporting by Ben Blanchard; Editing by Robert Birsel)