A 25-truck convoy carrying food and medical aid will enter the besieged, rebel-held town of Douma in Syria's eastern Ghouta on Thursday, Ziad Msallati, a senior adviser in the Syrian Arab Red Crescent, told Reuters on Wednesday.

A convoy with food and medicine managed to get into eastern Ghouta last week amid a massive army assault to recapture the enclave on the outskirts of the capital Damascus.

U.N. Syria adviser Jan Egeland, who is also head of the Norwegian Refugee Council, said the Syrian government had given its approval for a convoy on Thursday.