Thomas Bossert resigns from White House

The resignation comes just one day after newly appointed national security adviser John Bolton took over at the White House.

White House official Thomas Bossert, a special assistant to the president on homeland security matters, has resigned, the White House announced Tuesday.

The resignation comes one day after newly appointed national security adviser John Bolton took his position at the White House. Bloomberg has reported that Bossert’s resignation came as a result of a Bolton request.

Bossert spoke publicly as recent as Sunday on the Trump administration’s ongoing efforts to counter Russian aggression in cyberspace. Various national security experts, including some current U.S. officials, have criticized the White House in recent months for what they describe as insufficient punishment towards the Kremlin for having meddled in the 2016 presidential election.

Bossert was an important voice in the Trump administration when it came to cybersecurity-relevant decisions. He was previously involved in publicly announcing attribution for the WannaCry and NotPetya cyberattacks, which were respectively linked to North Korea and Russia.

Multiple current U.S. officials who spoke to CyberScoop, reacting to the resignation news, said that they were caught off guard by the decision. Some of these officials, all of whom spoke on condition of anonymity, explained that they first learned of the news from media outlets rather than from the White House.