Saudi Crown Prince Sultan bin Abdul Aziz has passed away, a palace announcement on state television said on Saturday\.
The crown prince, aged 86, also the minister of defense and aviation, had been in the United States since mid-June for medical treatment. According to AFP, he was operated on in July.
A half brother of King Abdullah, Sultan had spent long periods abroad for health reasons.
He died while the Saudi king, 87, remains in hospital in Riyadh, a week after he had an operation on his back.
The second in line to the succession, Prince Nayef, 78, another half-brother of King Abdullah who holds the portfolio of interior becomes the crown prince.
Prince Sultan's funeral will take place on Tuesday after his body is repatriated from the United States.