The EU and Turkey said that they are close to reaching a deal on how to ease the migration crisis at a summit in Brussels.
European Council President, Donald Tusk on Tuesday, said that irregular migrants arriving in Greece will be returned to Turkey.
For each migrant returned, Turkey wants the EU to accept a Syrian refugee on a one-for-one basis, and offer more funding and progress on EU integration.
Mr Tusk said that leaders had made a “breakthrough”, and he was hopeful of concluding a deal next week.
He said the progress sent “a very clear message that the days of irregular migration to Europe are over”.
Talks would continue ahead of an EU meeting scheduled for March 17 and 18.
Europe is facing its biggest refugee crisis since world war two. Most migrants came via Turkey, which is already sheltering more than 2.7 million refugees from the civil war in neighbouring Syria.