Saudi Arabia has replaced intelligence chief Prince Bandar bin Sultan, the kingdom's pointman on the Syrian conflict, "at his own request," the official SPA news agency announced Tuesday.
In a royal decree, the powerful official was "exempted... from his position at his own request" and replaced by his deputy, Yousef al-Idrissi.
Bandar, a former ambassador to the United States, is widely regarded as among the most influential powerbrokers in the Middle East and was appointed intelligence chief in 2012.
But he went abroad in December for health reasons, with diplomats saying he had been sidelined in Saudi efforts to support rebels fighting Syrian President Bashar al-Assad.
They said 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.
And in February, Prince Mohammed took part in a meeting in Washington of Western and Arab intelligence services to discuss Syria, confirming that Bandar had been shunted aside.
Bandar's management of the Syrian file had triggered American criticism and the matter with discussed during US officials' visits to the kingdom, diplomats said.
The prince himself reproached Washington for its decision not to intervene militarily in Syria, and for preventing its allies from providing rebels with much-needed weapons, according to diplomats.
Syrian state media and sympathisers in Lebanon have repeatedly lashed out at Bandar, accusing him of supporting Sunni Muslim radicals in Syria.
Saudi Arabia has been strongly supportive of the rebels battling Assad.
Over the years, Bandar achieved several major successes on the world stage.
For instance, he managed to convince Russia not to oppose UN resolutions to expel Iraqi troops from Kuwait following Baghdad's invasion of the emirate in 1990.
Bandar was also heavily involved in diplomatic contacts over the crisis in Lebanon that followed the 2005 assassination of former prime minister Rafiq Hariri, a key Saudi ally.
The outcry that followed the killing resulted in Syria's withdrawal of troops and intelligence agents from its smaller neighbour, ending a three-decade presence in a boost to Saudi interests.
Born in 1949, Bandar is son of the late crown prince Sultan bin Abdul Aziz, who died in 2011. He enjoyed close ties with then US President George Bush and his son, George W. Bush.