Mahathir, 98, was admitted to IJN on Jan 26 for treatment of an infection and observation.

In a statement, his office confirmed that he was discharged from IJN at 11.30am.

Mahathir has a history of heart problems, having undergone two  bypass surgeries in 1989 and 2007.

He had been admitted to IJN on a few occasions over the past three years to undergo medical tests.

Mahathir served twice as prime minister for a total of 24 years.