By Angus McDowall
RIYADH (Reuters) - Saudi Arabia's Prince Muqrin bin Abdulaziz, a former intelligence chief in the conservative Islamic kingdom, has been appointed deputy crown prince, Saudi state television reported on Thursday, making it more likely he will one day become king.
The appointment makes Muqrin, the youngest son of the kingdom's founder King Abdulaziz al-Saud, next in line to succeed in the world's top oil exporter and birthplace of Islam after his half-brothers King Abdullah and Crown Prince Salman.
"King Abdullah appoints Prince Muqrin as king in case the positions of king and crown prince become vacant," al-Arabiya television said, quoting a statement from the royal court.
The announcement gives more assurance to the kingdom's long-term succession process at a moment when sees itself as being a lone island of stability amid conflict and political turmoil across the Middle East.
King Abdullah turned 90 last year and Crown Prince Salman is 78. Muqrin was 70 last year.
Muqrin already holds the position of second deputy prime minister, a role to which he was appointed a year ago and was traditionally but informally seen as being equivalent to crown prince in waiting.
(Additional reporting by Stephen Kalin; editing by Andrew Roche)