As reported by the Lebanese newspaper, intelligence boss Saudis Prince Bandar bin Sultan bin Abdulaziz received a dose of poison, from which there is no antidote.
Some Lebanese media quoted sauditskie sources as saying that the prince received a dose of an unknown poison.
Bandar was in a coma, and through Morocco was brought to the U.S. for treatment.
Doctors say that the different treatments over the past few months could not cure him.
Sauditsky Prince is known for his close ties to former U.S. president George W. Bush, and was a supporter of the U.S. invasion of Iraq in 2003.
Bandar also considered a key figure and capacity to ensure the flow of arms from abroad supported the Syrian militants.