Washington ? The political pressure is growing against Attorney General Alberto Gonzales now that the first Republican senator has said President Bush should fire him over the dismissal of eight federal prosecutors.

The demand came Wednesday from New Hampshire Sen. John Sununu, a longtime critic of the administration’s treatment of civil liberties in the fight against terrorism. It followed days of Democratic calls that Gonzales step down over the Justice Department’s misleading response to the U.S. attorney firings.

“I think the president should replace him,” Sununu said in an interview with The Associated Press. “I think the attorney general should be fired.”

The White House reaction was curt – “We’re disappointed, obviously,” said spokesman Tony Snow – but unyielding.

At a news conference in Mexico, Bush stood by Gonzales, a longtime friend, and defended the firings.

“I do have confidence in Attorney General Gonzales,” Bush said. “What Al did and what the Justice Department did was appropriate.”

He said that what was “mishandled” was the department’s release to Congress of some but not all details of how the firings were carried out.

“Al’s got work to do up there,” on Capitol Hill, Bush said. “Mistakes were made. And I’m frankly not happy about them.”

Gonzales told reporters he would “work it out” with lawmakers so they understood the situation.

Yet even as Bush scolded the department for not being more forthcoming to Congress, his aides sought to protect White House political director Karl Rove and former counsel Harriet Miers from congressional subpoenas about their roles in the firings. The Senate Judiciary Committee was considering seeking subpoenas for Rove, Miers, deputy White House counsel William Kelley and five Justice Department officials.