The Air Force general who would have been the first from his service to command all U.S. forces in the Pacific is giving up his presidential nomination in the face of a fierce political fight between the Air Force and the Senate over a controversial deal with Boeing Co.

The Pentagon announced Wednesday night that Gen. Gregory S. Martin (search), who appeared at his confirmation hearing earlier in the day before the Senate Armed Services Committee, had requested that his nomination to succeed Adm. Thomas Fargo (search) as commander of U.S. Pacific Command be withdrawn.

The Pentagon statement gave no reason for the extraordinary reversal, but a spokesman for Air Force Materiel Command, which Martin has headed since August 2003, said Martin believed that questions raised at the hearing about his connection to the Boeing deal made his confirmation problematic.

Bryan Whitman, a spokesman for Defense Secretary Donald H. Rumsfeld, said Rumsfeld agreed to pull the nomination. He said no decision had been made on a new nominee for the Pacific Command job, which is responsible for U.S. military operations throughout the Pacific and portions of the Indian Ocean.

Martin would have been the first Air Force officer to hold the Pacific Command post, which has traditionally been held by a Navy admiral. Fargo is scheduled to retire this fall, but he apparently will remain until another nominee is chosen and confirmed by the Senate.

It's not clear whether Martin will remain at Air Force Materiel Command.

Martin's troubles at his confirmation hearing began with statements and questions posed by Sen. John McCain, R-Ariz. They pertained to a controversy over the Air Force's proposed deal with Boeing to lease 767 planes for use as aerial tankers, and to a scandal involving a former Air Force civilian official, Darleen Druyun, who was sentenced to nine months in prison Friday for helping Boeing obtain a lucrative contract in exchange for an executive job at the company.

Martin is not accused of wrongdoing in either matter, but McCain asserted that the general was "involved" in the $23 billion tanker lease arrangement. McCain pressed him so hard on the issues Wednesday that Martin concluded his confirmation would be held up for months, said Col. Jack Ivy, spokesman for Air Force Materiel Command.

"General Martin's overall assessment is that getting confirmed for U.S. Pacific Command would be difficult at this time," Ivy said. "So in the best interests of U.S. Pacific Command and the Air Force he requested that his nomination be withdrawn. It was clear from the comments made during the hearing that the tanker e-mail search has expanded, and until all of that has been cleared, the Senate Armed Services Committee is not expected to move forward on his nomination, which could take months."

McCain is in a long-running dispute with the Pentagon and the Air Force over his unfulfilled request for e-mail traffic about the 767 lease deal with Boeing. McCain has held up other Pentagon nominations over this issue, including that of Lawrence Di Rita for the job of assistant secretary of defense for public affairs.

McCain said he was upset with the Air Force for resisting his requests for e-mails relevant to the tanker lease discussions with Boeing.

"I hope that we can get the remaining e-mails," McCain said. "Actually, I don't know if we ever will or not, because the Air Force has been incredible in their unresponsiveness. But General Martin was involved in this."

McCain cited a letter to the committee from the Defense Department inspector general saying it had received more e-mails from the Air Force on Tuesday, and that it was "assessing the process used to search for documents sent to and from General Martin relating to acquiring a commercially derivative aerial refueling tanker."

McCain has asserted that the arrangement with Boeing amounted to a sweetheart deal that cost taxpayers billions of dollars more than if the Air Force had purchased aerial tankers instead of trying to lease them. He has pursued Air Force e-mails to build his case against the Boeing deal.

Druyun, a former Pentagon and Boeing official, pleaded guilty last spring to conspiracy and admitted that she began job talks with Boeing while she was overseeing negotiations on the tanker deal.

Martin worked closely with Druyun in 1998-99 while he held the position of principal deputy in the office of the assistant secretary of the Air Force for acquisition.

"I'm not an expert in contracting," Martin said in response to McCain's comments. "I saw nothing that she was doing that was inappropriate or in any way illegal."