The Department of Defense has been asked to provide information on the reported use of a personal, unofficial smartphone by President Donald Trump to communicate via his personal Twitter account.

In a joint letter sent to DoD Secretary James Mattis on Feb. 9, Sens. Tom Carper, D.-Del., and Claire McCaskill, D.-Mo., expressed concerns over reports that Trump continues to use an "old, unsecured Android phone" despite being provided a "secure, encrypted device approved by the U.S. Secret Service" prior to taking office.

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Noting the national security risks that would follow a compromised smartphone, as well as the need to document and maintain all presidential tweets as required by the Presidential Records Act, the senators have asked what steps the Defense Information Systems Agency has taken to secure presidential communications while preserving them for the National Archives and Records Administration.

As senior/ranking members of the Senate Committee on Homeland Security and Governmental Affairs, Carper and McCaskill have requested DoD provide written responses by March 9 on the situation, as well as all steps taken or planned by DISA in regard to protective measures on Trump’s communication devices.

The original letter can be viewed in its entirety on Carper’s website.