Saudi Arabia has replaced its intelligence chief, who is widely seen as the architect of the kingdom’s interventionist policy on the Syrian civil war. The government-owned Saudi Press Agency announced on Tuesday that prince Bandar bin Sultan had been “relieved of his post at his own request”. Bandar was born in 1946 to a concubine of crown prince Sultan bin Abdulaziz, 12th son of Saudi monarch King Abdulaziz.

In 1983, Bandar was appointed ambassador to the United States, a post he held until 2005. He developed numerous connections in Washington and rose to become a leading operator in Middle East affairs, enjoying to this day very close personal ties with Presidents George H.W. Bush and George W. Bush. In 2012 he was appointed director of the Saudi Intelligence Agency, the country’s primary intelligence organization.

Since that time, he has been the primary planner of Riyadh’s hawkish policy on the Syrian civil war, which has been to openly support the rebel groups fighting to oust the government of Syrian President Bashar al-Assad. Saudi Arabia began supplying weapons, cash and intelligence to the Syrian rebels as soon as Bandar took control of the country’s intelligence apparatus. But his once close relations with Washington went sour last year, when he described US President Barack Obama’s refusal to launch military strikes on Syria as a “major shift” in American Middle East policy.

He also angered the US by criticizing it’s rapprochement with the Islamic Republic of Iran, which is Riyadh’s major regional adversary. Perhaps most important of all, Bandar appears to have underestimated the strength of the al-Assad administration and over-confidently advising King Abdullah in 2012 that the Syrian government’s days were numbered. The stalemate in the Syrian civil war seems to have frustrated the Saudi government, which began to gradually distancing itself from Bandar’s musings since January.

The prince has spent most of 2014 in the United States and Morocco, ostensibly for “medical treatment”. According to Saudi government media, Bandar has been replaced “on an interim basis” by his deputy, Yousef al-Idrissi. Meanwhile, insiders report that the Syria file has been transferred to prince Mohammed bin Nayef, the kingdom’s minister of interior. It is worth noting, however, that Bandar remains secretary general of the National Security Council, an influential advisory board that directs Saudi Arabia’s national security, intelligence and foreign policy strategy.