DUBAI (Reuters) – Saudi Arabian Prince Saud al-Faisal, the world’s longest-serving foreign minister, has undergone a successful back surgery in the United States, the royal court said on Saturday.

Prince Saudi, 75, has been foreign minister since March 1975 and has played an important role in shaping the country’s response to many crises affecting the Middle East.

He is the second son of the late King Faisal bin Abdulaziz and a nephew of King Salman, who this week succeeded King Abdullah after his death.

“His royal Highness Prince Saud al-Faisal underwent a spine surgery in the United States and it was successful,” the royal court said in a statement carried by state news agency SPA. “He is undergoing physiotherapy which is normal following such a surgery,” the statement added, without giving further details on when or where the surgery had taken place.

Prince Saud’s uncle, King Abdullah, died in Riyadh on Friday. He was succeeded by his younger brother at a time when the world’s top oil exporter has pledged to maintain output levels despite a steep slide in world oil prices.

The kingdom, a Western-allied country and birthplace of Islam, also has joined a U.S.-led coalition against the Islamic State, a militant group based in Iraq and Syria that has tried to attack the Saudi border.

Prince Saud, who suffers from a chronic back complaint, underwent a surgery in 2012 to remove an intestinal obstruction caused by a previous operation.

(Reporting by Reem Shamseddine, writing by Sami Aboudi; Editing by David Gregorio)-thestar