Syrian Foreign Minister Walid al-Moallem has died at the age of 79, according to local media.

"The Ministry of Foreign Affairs and Expatriates mourns the death of Minister of Foreign Affairs Walid al-Moallem," said state news agency SANA on Monday, without giving any details.

The official announcement is yet to name the cause of al-Moallem's death, but the 79-year-old had for years been in poor health with heart problems. A source close to the Syrian government said it was widely expected his deputy, veteran diplomat Faisal Mekdad, would replace him as foreign minister.

Born in 1941, al-Moallem studied economics and political science at Cairo University in Egypt and graduated in 1963.

He started working in the Syrian Foreign Ministry in 1964 and had been sent to work with Syrian diplomatic missions in several foreign countries.

He served as the Syrian ambassador to the United States from 1990 to 1999, during which he participated in the Syrian-Israeli peace talks.

Al-Moallem was appointed foreign minister in 2006 and held the post until his death.

(With input from agencies)