China's shift brought a first sign of movement on any issue at the permanent 66-nation conference in more than a year, with Russia also signalling tentative approval of the "five ambassadors" proposal, the Italian president of the conference, Carlo Trezza, said.

"Other interested delegations have informed me that their capitals are studying with interest that suggestion," Trezza added.

The proposal, first tabled by Algeria, Belgium, Chile, Columbia and Sweden in July 2002, and revised since then, includes provisions to set up a special committee to look at the issue.

Chinese ambassador Hu Xiaodi said Beijing was willing to show flexibility by taking up the proposal, although it had previously rejected it on the grounds that it did not go far enough.

The United States earlier last year told the conference that it saw no need for new outer space arms control agreements, but has not taken a position on the "five ambassador" compromise since it was put forward.

Washington had stepped up its opposition in May 2001 when the Bush administration revived plans to set up a space-based missile defence system, which China and Russia claim could revive a new type of arms race.

Diplomats said the direction taken by Russia and China in Geneva could place further pressure for movement on the issue from the US.

The US has been favouring another topic before the conference, curbs on the production of fissile nuclear material, instead.

The conference, the only multilateral disarmament forum, has been deadlocked since completing the Comprehensive nuclear Test Ban Treatyin August 1996, failing to even agree on an agenda for further negotiations.

The prevention of an arms race in outer space is just one issue under consideration, with a range of other topics also blocked including overall nuclear disarmament.

Trezza said on Thursday countries must be prepared to consider "new items" to add to the agenda because of recent technological and geopolitical developments.

"We cannot -- it is the view of many -- shut our eyes in front of them."

Disarmament experts have expressed fears that some countries, including the United States, might develop "mini-nukes" which could take advantage of loopholes in the current global disarmament regime, or that terror groups could get hold of nuclear material for weapons.

SPACE.WIRE