European Council President Donald Tusk is due to visit Greece and Turkey as he tries to find a common approach to Europe’s worsening migration crisis.
Mr Tusk has said reducing the number of migrants travelling from turkey to the Greek islands is key to avoiding a humanitarian disaster.
More than 25,000 migrants are now stranded in Greece as border controls further north are tightened
Mr Tusk has been touring capitals in Central and South-eastern Europe this week, trying to ease tensions caused by the migration crisis.
His visits are seen as laying the groundwork for an EU-turkey summit on the issue on 7 march.