Following a request from a top House Democrat, the Pentagon’s inspector general office said on Thursday it will review a recent $400 million border wall contract for potential improper influence by the Trump administration.

On Dec. 4, Rep. Bennie Thompson, D-Miss., chairman of the House Homeland Security Committee, asked the Defense Department's inspector general to determine why the U.S. Army Corps of Engineers awarded Fisher Sand and Gravel Co. a contract to build part of the border wall along the southern perimeter of the Cabeza Prieta National Wildlife Refuge in Yuma County, Arizona. Previously, the Army Corps had reportedly determined the company’s offering was inadequate. The inspector general sent Thompson a letter announcing it will “initiate an audit of the solicitation and award of this contract.”

“The company had never been awarded a construction contract before and their wall prototype was late and over budget,” Thompson said in a statement. “Given the president’s multiple endorsements of this company and the amount of taxpayer money at stake, I remain concerned about the possibility of inappropriate influence on the Army Corps’ contracting decision. We must ensure that all laws and regulations were properly followed.”

The Army Corps has awarded $2.5 billion in border construction contracts since January 2017, but Thompson noted in his initial letter that Fisher Sand and Gravel Co. was not among the companies selected for the work. It “reportedly did not meet the operational requirements of U.S. Customs and Border Protection and its prototype came in late and over budget,” he wrote.

Thompson said that President Trump has repeatedly encouraged the department to select the company, despite its “history of red flags,” as reported by CNN. Additionally, Thompson said the president’s son-in-law and senior adviser Jared Kushner, who now oversees the construction, reportedly supported the contract award. A week before the contract was awarded, acting Homeland Security Secretary Chad Wolf toured a section of wall the company is building on private land through the conservative group We Build the Wall.

“These actions raise concerns about the possibility of inappropriate influence on [the Corps of Engineers’] contracting decision,” Thompson wrote.

Glenn Fine, Defense Department acting inspector general, said his office will formally announce the audit soon and will provide Thompson a copy of it upon completion.

Separately, the inspector general office said this week it is reviewing the legality of troop deployment and spending along the U.S.-Mexico border. Also, on Tuesday a Texas federal judge ruled that President Trump's declaration of a national emergency in January did not warrant his use of $3.6 billion in military construction funds to build the wall.