WASHINGTON — The Office of Inspector General for the Department of Defense will investigate a $400 million contract for border wall construction awarded to a North Dakota company after President Trump privately pushed the deal.

The chairman of the House Homeland Security committee, Representative Bennie Thompson of Mississippi, called for the inquiry into the decision made by the United States Army Corps of Engineers last week, raising concerns of “inappropriate influence.” Mr. Thompson wrote in a letter that Fisher Sand & Gravel “did not meet the operational requirements of U.S. Customs and Border Protection and its prototype project came in late and over budget.”

Glenn Fine, the principal deputy inspector general for the Department of Defense, wrote a letter to Mr. Thompson on Thursday saying the watchdog would investigate the contract for Arizona wall construction to see if it met solicitation standards.

“In response to your request, we have decided to initiate an audit of the solicitation and award of this contract,” Mr. Fine said in the letter to Mr. Thompson. “We are assessing the methodology of that audit and will formally announce the audit soon.”