One day after a spokeswoman said that Texas Gov. George W. Bush (R) would not sign an anti-tax pledge during his prospective presidential campaign, Bush told New Hampshire reporters that he had taken just such a vow in a letter to the head of Americans for Tax Reform.

Bush pledged in the letter to veto any corporate or individual income tax increases, if elected president. He also said he would oppose efforts to reduce or eliminate tax deductions and credits unless they are offset by rate cuts.

Bush's decision to take the pledge on the eve of his first campaign trip to New Hampshire demonstrated anew the potency of the tax issue in Republican primary politics and put him in the same position as his rivals for the nomination.

But given the statement by a Bush campaign official earlier in the week, the route he used to get to that position sparked criticism from some of his rivals.

Karen Hughes, the governor's press secretary, said the letter did not contradict Bush's long-standing policy of not signing pledges from advocacy groups. "He views his own words as pledges," she said. "He puts his own words and principles in writing. That's how he approaches these issues and that's what he did. In his letter, he did it in his own words."

But Grover Norquist, the head of Americans for Tax Reform, said: "It is, verbatim, the pledge. It was sent with that understanding. They put the pledge on a letter, signed it and sent it to me." Norquist added that his office had "asked for the exact wording and got it."

Bush's rivals, who earlier criticized him for not being willing to sign the anti-tax pledge, pounced yesterday when they learned of the latest development.

"Mr. Bush can either sign the pledge or not sign the pledge," said William Dal Col, campaign manager for Malcolm S. "Steve" Forbes. "He cannot have it both ways. That would be just like a Clinton politician, trying to have it both ways."

Ari Fleischer, spokesman for Elizabeth Dole's campaign, said: "Issues sometimes can be very difficult things. I think it's only fair to give the governor time to figure out where he stands."

Hughes said Bush preferred to define his positions in his own words and on his own timetable, "rather than reacting to the wishes and demands of [a particular] group." Asked why then he had made his position known in a letter to Norquist's organization rather than in a public statement, she said, "Because Grover had requested his position on this issue."

In 1988, Bush's father signed the tax pledge and used it against then-Sen. Robert J. Dole (R-Kan.), who had refused to do so. Later Bush made his famous "Read my lips, no new taxes" declaration, but broke it in 1990 in order to get a budget deal with Democrats.

Bush was asked in April whether his father's bigger mistake was in making the tax pledge in 1988 or breaking it. "I think making it, for certain," Bush responded in the interview. "Once he made it and broke it, it cost him a lot of credibility."

Did that mean he would not sign the tax pledge in New Hampshire? "It means if I do, I won't raise taxes." He added, "We haven't really forged our New Hampshire strategy."

Norquist said yesterday that he had been talking with Bush since last November. "They were always planning to take the pledge," he said. "They wanted to wait until the [Texas legislative] session was over."

An official of a rival campaign, speaking on condition that he not be named, said he hoped that when Bush sent the letter to Norquist, "He sealed the letter with his lips."

CAPTION: Texas Gov. George W. Bush made his anti-tax pledge in a letter to the head of Americans for Tax Reform.