Saudi Arabia s King Salman bin Abdulaziz al-Saud. AFP
Earlier in the day, the court said King Salman was suffering from "high temperature" and joint pain and would undergo medical tests at Al-Salam Palace in Jeddah.
It was the second time in less than a month that the Saudi government had commented publicly about the 88-year-old king's health.
The tests on Sunday "found that there was a lung infection", and doctors decided on "a treatment program consisting of antibiotics until the inflammation went away", according to the latest royal statement published by the official Saudi Press Agency (SPA).
King Salman has been on the throne since 2015.
Before that, his most recent hospitalization had been in May 2022, when he went in for a colonoscopy and stayed for just over a week for other tests and "some time to rest", SPA reported at the time.
King Salman underwent surgery to remove his gall bladder in 2020.
He was also admitted to the hospital in March 2022 to undergo what state media described as "successful medical tests" and to change the battery of his pacemaker.
King Salman had served as Riyadh governor for decades and also as defense minister.
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