Syrian Foreign Minister Walid al-Muallem has been admitted to the American University of Beirut Medical Center, Al Arabiya News Channel reported on Tuesday, citing Lebanese sources.
Last month, Muallem was rushed to the same hospital where he underwent tests for a suspected blocked coronary artery, Lebanese security officials and a lawmaker said.
The 73-year-old diplomat led the government's negotiating team at the failed Geneva peace talks this year. Muallem is known for his hardline stance against the opposition and is reportedly a close confidant of President Bashar al-Assad.
It is not clear if al-Muallem has had heart problems in the past.