WASHINGTON — The Army has agreed to a Pentagon investigation into claims by a top contracting official that a Halliburton subsidiary unfairly won no-bid contracts worth billions of dollars for work in Iraq and the Balkans, according to Army documents obtained Sunday.

The complaint alleges that the award of contracts to KBR, the Halliburton subsidiary, without competition to restore Iraq's oil industry and to supply and feed U.S. troops in the Balkans puts at risk "the integrity of the federal contracting program as it relates to a major defense contractor."

It also asks protection from retaliation for the whistle-blower, Bunnantine Greenhouse, chief contracting officer of the Army Corps of Engineers.

The Iraq contract with Halliburton has been a focus of the presidential campaign because of Vice President Dick Cheney's past ties to the company. Cheney was chief executive officer of Halliburton and continues to receive deferred compensation from the company.

In a letter to Greenhouse's lawyer, an Army attorney said that the matter is being referred to the Defense Department's inspector general for "review and action, as appropriate." It also said the Corps had been ordered to "suspend any adverse personnel action" against Greenhouse "until a sufficient record is available to address the specific matters" in her complaint.

Copies of the letter and complaints, documents which were provided to some members of Congress, were obtained Sunday by The Associated Press.

Halliburton spokeswoman Wendy Hall said from Houston, where the company is headquartered, "KBR doesn't have any information on what Bunny Greenhouse may or may not have said to other Pentagon officials in early 2003. Certainly we can't address any threatened legal action she may be considering against her employer."

"On the larger issues, the old allegations have once again been recycled, this time one week before the election," Hall said.

She emphasized that a report earlier this year by the Government Accountability Office, the auditing arm of Congress, concluded the Iraq contract had been properly awarded and she said the Balkans issue "was fully dealt with and resolved several years ago ... (and) since that time KBR has received high marks from the Army on our Balkans support contract."

Michael D. Kohn, who is Greenhouse's lawyer , in a letter to acting Army Secretary Les Brownlee, charged that in the Balkan contract a deputy assistant secretary of the Army had ordered changes in documents to legitimate the contract "for political reasons."

Kohn's complaint said contracts were approved over Greenhouse's reservations, handwritten on the original contracts, and extensions were awarded because underlings signed them without her knowledge and in collusion with senior officials.