CNN Business  — 

Former NSA director Gen. Keith Alexander has joined Amazon’s board, the company disclosed in an investor filing Wednesday.

Alexander’s role with the company reflects Amazon’s growing ties with Washington. In addition to leading the NSA during the Obama administration, Alexander was also the head of US Cyber Command. Alexander retired in 2014 and went on to found the private cybersecurity firm IronNet.

Alexander joins Amazon’s board as the company continues to wage a high-stakes legal battle with the Pentagon over a $10 billion military cloud computing contract, known as JEDI. The contract was awarded last year to Microsoft amid complaints from Amazon that the decision process was tainted by President Donald Trump’s improper political influence.

Last week, the Defense Department reaffirmed its decision to give the contract to Microsoft, prompting Amazon to say it will continue to protest the decision in federal court.