President Bush, accusing Democrats of breaking last fall's budget deal, threatened a flurry of vetoes on Friday to cancel any effects of a House vote limiting the authority of his budget office.

Bush told a meeting of House Republicans at the White House that a rules-change vote in the House on Thursday "undercut the credibility of the entire budget agreement," according to presidential spokesman Marlin Fitzwater."A deal is a deal. Let's stick by it," Fitzwater said.

The rule change, pushed through by majority Democrats over the strong objections of Republicans, gave to the Congressional Budget Office an accounting power that the budget pact had given to the White House office.

The budget agreement, a five-year $500 billion package of spending cuts and tax increases, gave the Office of Management and Budget the authority to make estimates of new program costs that would then be binding on both branches of government.

Such "score-keeping" authority is important, since the budget agreement has a pay-as-you go provision requiring that new spending on programs be offset by cuts in other areas or by tax increases.

The White House asserted that, by taking authority to project program costs away from the executive branch and giving it to the CBO, Congress was opening the way to hide the true costs of new programs.

Republican administrations have long contended that the CBO underestimates the costs of programs.

"Historically the liberals tend to use CBO estimates to provide low estimates of spending programs that when finally enacted or after enacted come out with huge price tags," Fitzwater said.

Congressional Democrats, on the other hand, have accused the White House office of making estimates influenced by politics.