More than 30,000 displaced in Syria's Idlib in latest offensive - U.N

U.N. humanitarian coordinator Mark Lowcock attends a news conference at the United Nations in Geneva, Switzerland, September 10, 2018. REUTERS/Denis Balibouse

BEIRUT/GENEVA (Reuters) - More than 30,000 people have so far fled their homes in northwest Syria since Syrian government and allied forces resumed air and ground bombardments there last week, the U.N. agency coordinating relief efforts said on Monday.

The U.N. Office for the Coordination of Humanitarian Affairs (OCHA) said an all-out military assault on the last major stronghold of active opposition to President Bashar al-Assad could set 800,000 people to flight. The OCHA chief, Mark Lowcock, warned that this risked provoking the worst humanitarian catastrophe of the 21st Century.