U.S. Special Envoy for Iran Robert Malley said on Thursday that his security clearance is under review and he expects the investigation to conclude "positively and soon." He added, "I have been informed that my security clearance is under review. I have not received any further information, but I expect the investigation to conclude positively and soon. In the meantime, I am on leave," confirming a tweet from a reporter from Axios news agency. Earlier, U.S. State Department spokesperson Matt Miller stated that Malley is on leave and is being replaced by Abram Paley, although it is unclear whether his leave has any repercussions on efforts to curb Iran's nuclear program following former President Donald Trump's decision to withdraw from the 2015 agreement and reimpose extensive sanctions on Tehran. However, CNN reported that Malley was forced to take unpaid leave on Thursday after his security clearance was suspended earlier this year amid an investigation into how he handled classified materials. Malley led the Biden administration's unsuccessful efforts to revive the nuclear deal, under which Iran had curtailed its nuclear program and made it difficult for it to acquire fissile materials necessary for creating a nuclear weapon in exchange for significant relief from sanctions. Tehran denies seeking to develop nuclear weapons. He had contributed to the drafting of the 2015 nuclear agreement and played a significant role in former President Bill Clinton's 2000 attempt to mediate a peace agreement between Israel and the Palestinians, an effort that failed. Western and Iranian officials stated earlier this month that the United States, after failing to revive the agreement, has conducted talks with Iran to ease tensions by outlining steps that would limit Iran's nuclear program, lead to the release of American citizens detained in Tehran, and unfreeze some Iranian assets abroad.