The Greek Prime Minister says it won't be possible to find a European solution to the migration crisis without Turkey.

The country hasn't been invited to an emergency EU summit tonight in Brussels.

The meeting between the corridor states comes amid attempts to curb the latest efforts by thousands of refugees to cross the Balkans.

Croatia and Slovenia are said to be "overwhelmed" by the numbers arriving in the last few days.

Alexis Tsipras isn't hopeful of a positive outcome tonight: 

Several states, including Slovenia, are threatening to close their borders if a solution is not found.

Russia is also not taking part, and has granted only a handful of Syrians asylum, despite continuing airstrikes in the country.

Plans include the deployment of more than 400 border guards within a week, and guarantees that countries will not transport refugees through to their neighbours. 

Speaking on her way into the meeting the EU's High Representative Federica Mogherini says she expects decisions to be made today:

10 EU leaders, including Angela Merkel, and the leaders of Albania, Serbia and Macedonia are taking part in today's extraordinary mini-summit.

The meeting was called by European Commission President Jean-Claude Juncker who said, "Europe today faces the greatest refugee flows it has seen since the Second World War. The countries along the Western Balkans route have been particularly exposed to these pressures".

More than 670,000 people have entered the Euro area so far this year, mainly fleeing violence in Syria, Iraq and Afghanistan.

Amnesty International is warning of a humanitarian disaster if migrants are stranded at borders throughout the winter.

Earlier this week, the United Nations Refugee Agency (UNHCR) said it does not have enough supplies for thousands of refugees in Serbia.

An estimated 10,000 people are in makeshift camps there after European countries limited the movement of people across their borders.

The EU has agreed a plan, resisted by Hungary and several other ex-Communist members of the bloc, to share out 120,000 refugees among its members, a small proportion of the 700,000 migrants the International Organization for Migration (IOM) projects will reach Europe's borders from the Middle East, Africa and Asia this year.