Amazon accused U.S. President Donald Trump of using "improper pressure" and bias that harmed its chances of winning a lucrative $10 billion contract from the U.S. Department of Defense.

Amazon said in a lawsuit unsealed Monday in the U.S. Court of Federal Claims that it lost the cloud computing contract, which was awarded to rival Microsoft, due to Trump's "personal vendetta against Mr. (Jeff) Bezos, Amazon, and The Washington Post."

Bezos owns Amazon and the Post. Trump has frequently attacked Bezos and Amazon for its low tax payments. and has accused the Post of spreading "fake news."

Amazon said in its lawsuit that Trump launched "repeated public and behind-the-scenes attacks to steer" the Pentagon cloud contract away from Amazon. It said Trump's interference made it impossible for the Department of Defense to choose a winner "reasonably, consistently, and in a fair and equal manner."

The suit is calling for the Pentagon to revisit its decision.

"The question is whether the president of the United States should be allowed to use the budget of DoD to pursue his own personal and political ends," the Amazon complaint states.

Pentagon spokeswoman Elissa Smith said in a statement Monday that the selection of Microsoft was made without external influence "by an expert team of career public servants and military officers."

The White House did not immediately comment on the lawsuit.

The high-stakes cloud computing project, formally called the Joint Enterprise Defense Infrastructure, or JEDI, is part of a Pentagon effort to store and process large amounts of classified data.

Amazon and Microsoft were the finalists for the project after Oracle and IBM were eliminated from contention.