Two Republican lawmakers are pressing the attorney general to investigate potential anticompetitive behavior by Amazon . com Inc. in its pursuit of a major government cloud-computing contract, according to letters reviewed by The Wall Street Journal.

Sen. Mike Lee (R., Utah) and Rep. Ken Buck (R., Colo.) urged Attorney General Merrick Garland to open up an investigation into the Joint Enterprise Defense Infrastructure procurement process in a joint letter on Monday evening. Amazon was one of a number of technology companies that competed for the Department of Defense’s 10-year, $10 billion cloud-computing contract, but ultimately lost to rival Microsoft Corp.

The letter says Amazon might have violated antitrust laws and federal conflict-of-interest laws. “We are concerned that Amazon may have attempted to monopolize one or more markets relating to government and/or commercial cloud computing services by improperly influencing the Joint Enterprise Defense Infrastructure procurement process,” the letter says.

“These are the same false, tired, and meritless allegations that have been repeatedly rejected by every independent review” in federal courts and by government agencies, an Amazon representative said Tuesday.

Amazon has contested the 2019 decision awarding the so-called JEDI contract to Microsoft, its largest cloud-computing rival. Amazon contends that it was treated unfairly in the JEDI procurement process, claiming that former President Donald Trump improperly influenced the outcome and steered the contract to another bidder. The Pentagon has denied those claims.