Saudi King Abdullah will undergo another surgery on his back in the United States on Friday, the royal court said as reported by AFP.
The king travelled to New York ten days ago to receive treatment for a blood clot on the spine and a herniated disc after he suffered from back problems for around two weeks.
"King Abdullah will undergo surgery on several vertebrae in his spine in a follow-up to his previous operation, as part of the treatment plan set by the medical team,'" the court said in a statement carried by the official news agency.
In his absence Crown Prince Sultan bin Abdul-Aziz, who has himself been undergoing cancer treatment for years, and spends much of his time in Morocco, will manage state affairs.
The 86-year-old monarch became king in 2005, but has been running Saudi affairs since the mid-1990s when his half-brother, King Fahd, suffered a massive stroke.