Nato is ready to patrol the Aegean Sea to deter people-smugglers taking migrants from Turkey to Greece, US Defence Secretary Ashton Carter says.
The announcement followed a request from Nato members Turkey, Germany and Greece.
Nato defence ministers are meeting in Brussels.
Plans will be drawn up by the alliance’s military authorities for review and possible implementation, Mr Carter said.
He told a press conference that targeting the “criminal syndicate that is exploiting these poor people” would have the greatest humanitarian impact.
Almost 75,000 migrants and refugees have already arrived in Greece by sea in 2016, the UN refugee agency says.