President Biden's Special Envoy for Iran Robert Malley has been placed on leave amid an investigation into his security clearance, Malley confirmed to Fox News on Thursday.

Malley, who has served in the position since January 2021, played a significant role in the Biden administration's efforts to revive the 2015 Iran nuclear agreement. In 2018, then-President Donald Trump opted to kill the deal and reimpose sanctions on Iran.

State Department Spokesperson Matthew Miller confirmed to Fox News that Malley, who helped develop the 2015 nuclear pact, is on leave.

"Rob Malley is on leave and Abram Paley is serving as acting Special Envoy for Iran and leading the Department’s work in this area," Miller said.

Malley confirmed that his clearance is being investigated, but said he was confident about a positive outcome.