Saudi Arabian intelligence chief Prince Bandar bin Sultan, the architect of Riyadh's attempts to bring down Syrian President Bashar al-Assad, has been removed from his post, state media reported Tuesday.

His departure, months after he was quoted warning of a "major shift" from the United States over its Middle East policy, may help smooth relations with Washington as Riyadh pushes for more U.S. support for Syrian opposition fighters.

"Prince Bandar was relieved of his post at his own request and General Youssef al-Idrissi was asked to carry out the duties of the head of general intelligence," state news agency SPA said, citing a royal decree.

The decree did not say if Bandar would continue in his other position as head of the National Security Council. A former ambassador to the U.S., Bandar was appointed intelligence chief in July 2012, in charge of helping Syrian rebels bring down Assad — who is an ally of Riyadh's biggest regional rival, Iran.

Saudi media reported that the Syrian dossier has been transferred to the interior minister, Prince Mohammed bin Nayef, who cracked down on Al-Qaeda following a wave of deadly attacks in the Gulf state between 2003 and 2006.

Syrian state media in Lebanon have repeatedly lashed out at Bandar, accusing him of supporting Sunni Muslim radicals in Syria. He was also closely involved in Saudi support for Egypt's military rulers after they ousted Islamist President Mohamed Morsi last year, diplomatic sources in the Gulf have said.