US special envoy for Iran says his security clearance under review

US Special Envoy for Iran Robert Malley said on Thursday his security clearance is under review and that he expects the investigation to end "favorably and soon."

"I have been informed that my security clearance is under review. I have not been provided any further information, but I expect the investigation to be resolved favorably and soon. In the meantime, I am on leave," he said, confirming a report tweeted by a reporter for the Axios news organization.