Washington, Aug 7 : US Secretary of State Mike Pompeo said on Thursday that Brian Hook, Washington's special envoy for Iran, has decided to step down from the post. "Brian Hook has decided to step down from his role as the US Special Representative for Iran and Senior Advisor to the Secretary," Pompeo said in a statement on Thursday, without giving a reason for Hook's departure. Pompeo added that Elliott Abrams, US special envoy for Venezuela, will also take on Hook's position following a transition period, reports Xinhua news agency. Hook has served as the special envoy for Iran and senior policy advisor since August 2018, and before that he was director of the policy planning staff in the State Department. In a report, the New York Times said that the resignation of Hook "appears to bury any remaining chance of a diplomatic initiative with Iran before the end of Trump's term". Hook's departure also came as President Donald Trump's administration was seeking to extend an international arms embargo on Iran despite a lukewarm support for the bid. Pompeo said on Wednesday that the US would present a resolution in the UN Security Council next week to extend the arms embargo, and he also threatened to trigger the snapback mechanism in the 2015 Iran nuclear deal to reimpose UN sanctions against Tehran. Under UN Security Council Resolution 2231, the arms embargo will be lifted this October. Tehran said it would not accept a renewal of the embargo. /IANS