Millions around the world are already relying heavily on food aid to survive, the United Nations World Food Programme (WFP) has warned.
David Beasley, head of the (WFP), said urgent action was needed to avoid a worldwide catastrophe.
The report estimates that the number of people starving could almost double - from 135 million to more than 250 million.
Turkish and Russian military forces have carried out another joint patrol along a key highway in northwestern Syria, said Turkey's Defense Ministry on April 21.
"Fifth combined Turkish-Russian land patrol was conducted today by air and ground vehicles on M4 motorway in Syria's Idlib province, as part of the earlier TR-RF agreement," the ministry said on Twitter.
Forty-seven unaccompanied asylum-seeking minors were relocated from Greece to Germany Saturday.
Germany's interior minister, Horst Seehofer, said the evacuation was "the result of months of preparation and intense talks with our European partners" and expressed hope that other countries would also begin taking in refugee children soon.