Malaysia's nearly 100-year-old former prime minister Mahathir Mohamad was discharged from hospital Monday, almost two months after he was admitted for an infection, his office said.

The 98-year-old, dubbed the world's oldest serving leader when he became prime minister for the second time in 2018, was admitted to the National Heart Institute on 26 January.

"Mahathir will be resting at home for a while," an aide told AFP on condition of anonymity.

Mahathir's office shared photos of him reading newspapers and writing notes when his prolonged admission sparked concerns.

He thanked Malaysians for their prayers and well wishes in a brief message last Monday ahead of the Muslim fasting month of Ramadan.

Mahathir first led Malaysia from 1981 to 2003 and then came out of retirement to lead a reformist coalition that toppled the scandal-tainted rule of Najib Razak in 2018.

He became prime minister again that year at the age of 92, but his coalition collapsed two years later due to infighting.

Mahathir lost his parliamentary seat in a shock defeat in 2022 but continues to be active in politics and has emerged as a leading critic of Prime Minister Anwar Ibrahim.

He was also admitted to hospital in December 2021, January 2022 and August 2023 for medical checks.

Mahathir has had numerous heart problems over the years, suffering several heart attacks and undergoing bypass surgery.