WASHINGTON (Reuters) - Northrop Grumman Corp (>> Northrop Grumman Corporation) Chief Executive Wes Bush on Wednesday lauded the U.S. government for approving exports of some unmanned aerial vehicles, or drones, and said more work was needed to keep up with technological advances in other countries.

Bush said U.S. defense officials increasingly recognized the need to update U.S. policy given the availability of drones from other countries, and said State Department officials were also awakening to changing realities in the global market.

But he told a conference hosted by the Brookings Institution that more work was needed to address U.S. industry's concerns that it is losing market share due to bans on the export of larger drones.

The main sticking point is the Missile Technology Control Regime, or MTCR, a partnership among 34 countries that was established in 1987 to prevent the proliferation of missiles capable of carrying a 500 kg (1,102 pound) payload at least 300 km (186 miles). The rules were amended in 1992 to include larger unmanned aerial vehicles.

Northrop, which builds high-altitude Global Hawk drones, and other firms have long urged changes that would allow them to compete with Israel, the leading exporter, and other countries.

The U.S. government has been reluctant to tinker with the export controls for fear it may allow sensitive technology to fall into hostile hands, but industry and government officials say a revamped policy on exports may be released soon.

Bush welcomed the U.S. government's support for sales of Northrop's Triton unmanned system to Australia, and recent interest in the Global Hawk system from Japan and South Korea.

"I do see a lot of progress," Bush said. "We still have some work to do in front of us, but it's on the right vector."

Bush said most U.S. officials now realized it was better to work with allies on developing unmanned technologies than ring-fencing technologies that were available elsewhere.

Speaking with Reuters after the event, Bush urged the government to develop a "firm set of principles against which we can all operate," and said U.S. companies needed a broad understanding of how a new policy would be implemented.

Bush said the U.S. government's interest in expanding ties with India could pave the way for drone exports to that country, but industry needed more than just isolated waivers.

He said President Barack Obama's nominee for defense secretary, Ashton Carter, had been a leader on the issue of drone exports during his previous tenure at the Pentagon.

(Reporting by Andrea Shalal)

By Andrea Shalal

Stocks treated in this article : Northrop Grumman Corporation, Textron Inc.