The official, Charles Smith, said he was ousted from his position as the top civilian overseer of KBR's lucrative contract to supply services to U.S. troops when he refused to sign off on more than $1 billion in questionable spending, The New York Times reported Tuesday.

Smith said KBR lacked credible data to back up its spending and so he decided to impose escalating penalties on the company, which had been called Kellogg, Brown and Root and was a subsidiary of Halliburton Corp., the former employer of U.S. Vice President Dick Cheney. But, Smith said he was soon replaced in his job and his successor eventually awarded the payments KBR was seeking, the newspaper said.

KBR's government contracts in Iraq have been a point of debate in the U.S. Congress, with some elected officials contending the company isn't able to justify its costs.

Army officials denied Smith was removed because he questioned KBR's activities and a company spokeswoman told the Times KBR committed no improper behavior.