Two leaders of the Senate Appropriations Committee have denounced Defense Secretary Donald H. Rumsfeld's plan to defer funding for two new medium-weight Army combat brigades in the fiscal 2004 budget.

In the opening salvo of this year's defense budget debate, Sen. Ted Stevens (R-Alaska), the committee's incoming chairman, and Sen. Daniel K. Inouye (D-Hawaii) said in a Jan. 6 letter to the Pentagon that failing to fund the brigades -- built around new eight-wheeled Stryker combat vehicles -- would violate a mandate in the current defense budget. It requires the funding of six Stryker brigades over the next five years.

Three of the high-tech brigades have already been funded, at a cost of about $1.5 billion each, and Rumsfeld has committed to funding a fourth in fiscal 2004.

In the letter addressed to Deputy Defense Secretary Paul D. Wolfowitz, the senators also said the decision to defer or eliminate funding for the other brigades "is yet another example of the disregard of the Congress, and existing law, by the senior leadership of the Defense Department."

A senior defense official responded that a final commitment for the fifth and sixth Stryker brigades has been deferred only so that options for increasing the Stryker brigades' combat power could be considered. It is possible that beefing up the first three brigades would prove so costly that the fifth and sixth would be scrapped, the official said, but the intention is to "end up with six brigades more capable than the original design."

The official said the consultation with senior congressional leaders has been extensive, if not unprecedented, in recent months. "Their views are going to be taken extremely seriously," he said.

The dispute over the Stryker brigades illustrates how the Rumsfeld-Wolfowitz agenda for "transforming" U.S. military capabilities for the digital age has triggered conflict on Capitol Hill, where powerful lawmakers typically favor existing weapons systems manufactured or based in their states and home districts.

The third Stryker brigade will be based next year in Alaska, and the fifth is scheduled to be based later in the decade in Hawaii.