The heir to the Saudi throne, Crown Prince Sultan bin Abdel Aziz, has died after an illness, state TV said Saturday. He was 85 years old.
The death of the crown prince -- half brother of the ailing Saudi King Abdullah -- opens questions about the succession in the oil-rich kingdom.
Sultan, who was the kingdom's deputy prime minister and the minister of defense and aviation, had a string of health issues. He underwent surgery in New York in February 2009 for an undisclosed illness and spent nearly a year abroad recuperating in the United States and at a palace in Agadir, Morocco.
The report did not say where outside the kingdom he died or elaborate on Sultan's illness, but he had been in the United States for medical treatment since June.
"With deep sorrow and sadness the Custodian of the Two Holy Mosques King Abdullah bin Abdulaziz mourns the death of his brother and his Crown Prince Sultan," said the statement carried on state news agency SPA and state television.
The most likely candidate for the throne after Sultan is Prince Nayef, the powerful interior minister in charge of internal security forces. After Sultan fell ill, the king gave Nayef an implicit nod in 2009 by naming him second deputy prime minister, traditionally the post of the third in line.
Anyone who rises to the throne is likely to maintain the kingdom's close alliance with the United States. But there could be internal differences. Abdullah has been seen as a reformer, making incremental changes to improve the position of women, for example, and to modernize the kingdom despite some backlash from the ultra-conservative Wahhabi clerics who give the royal family the religious legitimacy needed to rule. Nayef, for example, is often seen as closer to the clerics.