President Bush may veto any NASA budget bill that attempts to cut or eliminate spending on his proposed new space plan, United Press International has learned.

Office of Management and Budget Director Josh Bolten sent a letter Thursday to House Appropriations Committee chairman C. W. Bill Young, R-Fla., as well as other House members, saying senior White House aides would urge Bush to veto any measure that cuts spending for the new space exploration effort.

The budget the committee passed Wednesday slashed $1.1 billion from the president's request, eliminating every element of the space plan.

The bill, which also contains spending for veterans and housing, now heads to the House floor House for a vote. The Senate could pass a similar version this fall.

Rep. Tom Delay, R-Texas, the House Majority Leader and a strong supporter of the Bush space proposal, vowed to fight any bill with deep NASA cuts.

This is the first time any U.S. president has threatened to veto a spending bill because it contained too little space money. The threat suggests the administration is committed to its space proposal and may risk an election-year fight -- even with Republican leaders -- to save Bush's space program.

The proposed increase for NASA in next year's federal budget is the only spending boost proposed for any domestic agency not involved in homeland security or national defense.