Updated

After achieving what officials compare to "a bullet hitting a bullet" over the weekend, a test of the missile defense shield supported by President Bush has some congressional leaders vowing to put the technology on a fast track to approval.

The missile interceptor, launched from Kwajalein Atoll in the Pacific Ocean, hit its mock warhead target in space after it was fired from Vandenberg Air Force Base in California – nearly 5,000 miles away.

The success of the interceptor, which follows two failed tests during the Clinton Administration, has bolstered missile defense supporters.

Sen. Trent Lott, R-Miss., told Fox News Sunday that he sees the test's success as a first step towards convincing American allies in Europe and Russia that "we need to move beyond the old way of thinking … we need a new strategic alliance on how we have missile defense."

Some European and Russian leaders have expressed concerns that American missile defenses violate the 1972 Anti-Ballistic Missile (ABM) Treaty with Moscow. And some critics worry that pursuing a defense shield could exacerbate nuclear threats posed by nations such as Russia, Iraq and North Korea, and that it could damage diplomatic relations with China and Russia.

Lott also told reporters that Senate leaders in favor of President George W. Bush's $9 billion missile defense plan will place it "right at the top of the agenda" and hope it will "not be allowed to be pushed aside by Democrats." Bush is hoping to build the system by 2004.

Bush's proposal would deploy a multilayered shield, including missiles launched from ships and lasers fired from modified 747 aircraft, in order to defend both the U.S. and its allies from nuclear attack.

But Lt. General Ronald Kadish, head of defense missile programs, cautioned that "this is one in a series of tests and we need to plan for the future of these things … no one test makes a difference."

And Sen. Joseph Biden, D-Del., argued against reading too much into the weekend's test.

"Some of us are a little skeptical, and some of the people in the scientific community are very skeptical."

But Sen. Joseph Lieberman, D-Conn., has broken with some of his Democratic colleagues and says he supports developing a shield.

Lieberman congratulated Kadish and his team for a "significant step forward" and called it "very encouraging news."

He added that "there is a missile threat and we need to develop a defense to it."

Fox News' Kelley O. Beaucar, Steve Centanni and The Associated Press contributed to this report.