Brian Hook is stepping down from his post as special US envoy for Iran as the Trump Administration shifts into top gear to impose an even tighter clampdown on the Islamic Republic. US Secretary of State Mike Pompeo said in a tweet that Hook, 52, was moving to the private sector. He will be replaced by Elliott Abrams, a longtime – and often controversial – Washington troubleshooter who is currently the administration’s point man for Venezuela. The US is lobbying other members of the United Nations Security Council to vote for an extension of an arms ban against Iran that is due to lapse in October under a 2015 multilateral accord aimed at preventing Tehran from developing nuclear weapons. Few, if any, of these countries appear ready to extend the ban, and Washington’s veto power in the Council would be useless. To work around this, the Trump Administration is reportedly planning to trigger the accord’s so-called snapback mechanism, which would renew all sanctions against Iran that were canceled under the agreement. Yet Washington pulled out of the accord in 2018, saying it was insufficiently strict, and the remaining signatories – France, the UK, Germany, Russia, China and the European Union – say this means the US no longer has any say in the matter.