WASHINGTON (Reuters) - U.S. Senate Armed Services Committee Chairman John McCain on Thursday urged Defense Secretary Ash Carter to investigate what he called troubling remarks by a former senior United Launch Alliance executive about his company’s dealings with the Pentagon.

U.S. Senator John McCain speaks at the Munich Security Conference in Munich, Germany, February 14, 2016. REUTERS/Michael Dalder

Brett Tobey resigned Wednesday as vice president of engineering for ULA, a joint venture of Lockheed Martin Corp and Boeing Co, after his comments at a Colorado university were posted by Space News, a trade publication.

In his remarks, Tobey contradicted ULA’s reason for skipping a competition to launch GPS satellites and said the Defense Department “bent over backwards to lean the field” to ULA’s advantage in that competition with new market entrant SpaceX.

He also said the Pentagon was trying to figure out “how do we silence McCain,” who has urged the government to penalize ULA for failing to bid in the competition despite receiving $800 million in support funding for launch services every year.

“This committee treats with the utmost seriousness any implication that the Department showed favoritism to a major defense contractor or that efforts have been made to silence members of Congress,” McCain told Carter at a hearing on the U.S. Defense Department’s fiscal 2017 budget request.

ULA said Tobey’s remarks were inaccurate.

ULA, the sole provider for U.S. military launches for nearly a decade, is scrambling to restructure so it can compete with Space Exploration Technologies, or SpaceX.

ULA last year said it had skipped the GPS-3 launch competition because it lacked the required accounting systems and did not have enough Russian-built RD-180 engines to power its Atlas 5 rockets due to a ban imposed by Congress after Russia’s annexation of the Ukraine region of Crimea.

Tobey said ULA did not want to get into a “price shootout” with SpaceX since its launches cost $125 million, or close to $200 million including the separate launch support contract, compared to around $60 million for SpaceX.

Carter did not respond to McCain’s request for a “full investigation” into the comments from the former ULA executive.

Winston Beauchamp, deputy undersecretary of the Air Force for space, had no immediate comment on Tobey’s remarks.

He said the Air Force had concluded it could not penalize ULA for not bidding in the GPS-3 launch competition since there was no requirements for companies to bid. He also noted that the launch support contract was solely associated with launches already awarded to ULA under an earlier block buy contract.