The Pentagon is seeking a 20 percent boost in funding for the program, from 7.7 billion dollars this year to 9.2 billion dollars in 2005, under the proposed budget presented to Congress on Monday.
Plans calls for deploying 20 ground-based interceptor missiles and up to 10 sea-based missiles by the end of fiscal 2005.
The Pentagon anticipates declaring the system to have an "initial operational capability" by the end of fiscal 2004 on October 1.
"Probably about June or July is when the first (interceptor missiles) will go in," said Rick Lehner, a spokesman for the Missile Defense Agency. "You still have a period of check-out before their declared ready for operational use."
Work to upgrade a Cobra Dane radar at Shemya Island in the Aleutians and an early warning radar at Beale Air Force Base in California -- integral to the system's tracking and targeting of incoming missiles -- are supposed to be complete by the end of the summer, he said.
But the Missile Defense Agency plans only two full fledged intercept tests before the system is declared operational.
The Pentagon's chief of weapons testing and evaluation, Thomas Christie, warned in a report last month that "the small number of tests will limit confidence in the integrated interceptor performance."
The interceptor missile will be blasted into space on a commercial booster developed by Orbital Science that has not been tested before in a full-fledged intercept test.
Its first such test will be in the May-June period -- just before the first of the missiles are supposed to go into launch silos -- and a second intercept test will be conducted in mid to late summer, Lehner said.
"We haven't done an intercept test since December of 2002 because there was no point in using a surrogate booster. We wanted to wait at least until we had an operational booster," Lehner said.
"Now that the Orbital one is ready we can resume intercept testing again," he said.