Defense Secretary Donald H. Rumsfeld has granted the agency that is overseeing development of a national missile defense system extraordinary freedom from normal Pentagon procedures for controlling and monitoring new weapons programs.

Under the special authority, the agency will be exempt from regulations that compel military commanders to specify requirements for new weapons. The agency also will not be subject to traditional reporting about program timelines and costs. And many of its testing efforts will be free from oversight by the Pentagon's test evaluation office.

The unusual exemptions, outlined in a memo from Rumsfeld released with little fanfare last month, illustrate how the Bush administration is proceeding apace with plans to accelerate development of a national missile defense system -- its chief defense policy objective before last September's attacks -- even as it wages global war on terrorism.

But the wide latitude the administration has given missile defense planners to skirt traditional Pentagon accountability and oversight rules also has drawn warnings from watchdog groups and some members of Congress concerned that the Pentagon is handing missile defense officials what amounts to a blank check.

The Bush administration is spending $7.8 billion on missile defense research and development in the current fiscal year, up $2.5 billion from a year ago, and has asked Congress for an additional $7.8 billion for the fiscal year that begins Oct. 1.

E.C. "Pete" Aldridge, the Pentagon's undersecretary for acquisition, said the moves were intended to streamline oversight activities that too often have imposed intrusive paperwork, overlapping requests for information and other unnecessary and time-consuming demands on missile defense authorities.

"We needed to give them a process by which they could put all these things together without all the encumbrances of having so much oversight and so many briefings that have to be done at multiple levels," he said in an interview.

Some in Congress, however, are already expressing doubts about the wisdom of the Pentagon's rationale and say the measures may require additional legislation.

"It raises a whole set of questions," said a senior Democratic staff member in the Senate. "They're getting out of many of the checks and balances that usually apply in major weapons development."

Aldridge said he could think of no other Pentagon program that has such exemptions. He drew an analogy with establishment of the National Reconnaissance Office, which was set up in great secrecy in the 1960s to develop and operate spy satellites.

"While we can't do exactly the same thing with missile defense, the concept is still similar," he said. "So we need to make sure that they have all the mechanisms they have to make decisions quickly, appropriately and in a way that they can solve this very difficult problem."

Further underscoring the high priority the administration is placing on the missile defense program, Rumsfeld's memo elevated the Pentagon group responsible to full agency rank and changed its name -- from Ballistic Missile Defense Organization to Missile Defense Agency. The memo directed that the agency be staffed at 100 percent of authorized levels, a significant move in a department where many branches make do with personnel slots unfilled.

"The special nature of missile defense development, operations and support calls for nonstandard approaches to both acquisition and requirements generation," the memo said.

Asked why the missile defense effort should receive such exceptional treatment, Aldridge replied, "National priority." A second reason for assigning special status to the initiative, he said, is the particularly complex nature of its mission to invent not just a single anti-missile weapon but "a system of systems" for defending the United States against attack.

The administration intends to pursue a host of possible weapons -- land- and sea-based interceptors, airborne lasers and space-based devices -- aimed at knocking down enemy warheads in various stages of flight.

Rumsfeld's memo made clear that the Missile Defense Agency director -- a three-star position currently filled by Air Force Lt. Gen. Ronald Kadish -- will be in charge of shepherding the programs through their experimental phases. Once deemed ready for procurement, the plan is to turn control of the weapons over to the Army, Navy or Air Force. At this point, they would be subject to normal oversight procedures.

Rumsfeld also reserved the right of the secretary of defense to approve use of any of the experimental test assets for "contingency or emergency deployment." Administration officials have made no secret of their desire to have in place as early as 2004 a new testing facility in Alaska that could also constitute a rudimentary defense against North Korean missiles.

Normally, work on a new weapon system is guided by detailed operational requirements that, in turn, are based on specific projected threats. Instead, the Bush administration intends to define a more general set of capabilities and attempt to reach them in phases or developmental "blocks" spaced in two-year intervals.

The decision to dispense with normal Pentagon performance requirements, critics say, is like putting the cart before the horse. "Rather than first spell out what's needed, it sounds like they're just going to create something and then say this is something we need," said Lisbeth Gronlund, a missile defense specialist with the Union of Concerned Scientists. "In effect, they're saying: 'Whatever you've got, we'll take.' "

Several members of the Joint Chiefs also expressed reservations last year when first briefed by Rumsfeld and Kadish on the new approach, according to participants. They worried that the missile defense organization might stop short of developing an optimal system and settle for something insufficient. They also were wary of handing the agency billions of additional dollars without some way of controlling how the money would be spent.

To protect the services' interests in the Missile Defense Agency's programs, Rumsfeld has established a high-level oversight group called the Senior Executive Council, consisting of the service secretaries as well as the deputy secretary of defense and the undersecretary for acquisition. He also has set up an advisory team -- the Missile Defense Support Group, which includes senior representatives from such Pentagon offices as finance, policy, personnel and acquisition.