INTERVIEW-Test paves way for U.S. to buy more missile defense interceptors

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WASHINGTON, June 24 (Reuters) - Sunday's successful intercept test of the U.S. missile defense system will allow the Pentagon's Missile Defense Agency to buy 14 more ground-based interceptors as planned, the Defense Department's top financial official told Reuters on Tuesday.

Pentagon Comptroller Robert Hale said the fact that the Boeing Co-run system hit and destroyed a dummy missile for the first time since 2008 was good news, but further tests were needed to improve confidence in the system, the sole U.S. defense against long-range ballistic missiles.

"It certainly paves the way," Hale said in an interview at his Pentagon office. "If we had had continued failures, we would have had to rethink. But I think our plan now remains to buy the original 14 interceptors."

Hale said the Boeing-run Ground-based Midcourse Defense (GMD) system had clearly faced problems and Pentagon leaders had discussed at length efforts now underway to improve the system.

Reuters reported last week that the Pentagon is restructuring a $3.48 billion contract with Boeing for management of the missile defense system to put more emphasis on maintenance and reliability.

He said Sunday's test was seen as "reasonable" and the results were positive, but the system needed to further tests before U.S. officials could have full confidence in the system.

"It's got to work several times. We've got to demonstrate it under various conditions before we'd have ... full confidence in the system," Hale said. "That is the ultimate accountability."

Critics have urged Congress and the Pentagon to halt plans to buy 14 more interceptors until a new, more reliable warhead or "kill vehicle" is developed for the system.

The Raytheon Co kill vehicle that struck the dummy missile on Sunday failed in its two previous tests. An earlier version failed during a July 2013 test.

The Government Accountability Office, the investigative arm of Congress, has also raised concerns about the structure and oversight of the Missile Defense Agency, which is not governed by the same acquisition rules as other major weapons programs.

Hale said his "gut feel" was that the missile defense program should be subject to the same rules as its weapons systems moved into production.

(Reporting by Andrea Shalal; Editing by Eric Beech)