Saudi Arabia's King Salman bin Abdulaziz will undergo medical tests on Sunday due to "high temperature and joint pain," state news agency SPA reported.

The examinations will be conducted at the royal clinics at Al Salam Palace in Jeddah. The king, 88, was last admitted to hospital in April for a routine checkup, state TV reported then.

King Salman, the custodian of Islam's holiest sites, became ruler of the world's top oil exporter in 2015 after spending more than 2 1/2 years as the crown prince and deputy premier.