The European Union hopes this week to strike a contentious deal with Turkey aimed at curbing the flow of migrants into Europe.
The country has been the last stop for migrants before attempting the treacherous crossing of the Aegean Sea to reach EU member state Greece.
The plan is the bloc's latest attempt to control its migration crisis, after more than 1 million migrants and asylum seekers reached European shores last year.
Here is what the EU has done so far.
EU-TURKEY ACTION PLAN: The EU and Turkey agreed in October already to cooperate on stemming migration flows. The EU offered Turkey 3 billion euros (3.3 billion dollars) in refugee aid and promised to boost relations with the country, in return for efforts by Ankara to curb the migration flows. But the deal has had no obvious impact on arrivals.
Under the new plan being considered this week, all future migrants and asylum seekers arriving in Greece from Turkey would be sent back. For every Syrian returned in this way, the EU would directly accept another Syrian asylum seeker out of Turkey. Under the deal, Ankara has also sought concessions on visa-free EU travel and its bid to join the bloc.
BORDER CONTROLS: The EU has struggled to adequately guard its external borders, with Greece particularly overwhelmed by the migrant arrivals from Turkey. The EU border agency Frontex has received more resources and deployed to Greece. Frontex is supposed to be expanded and upgraded into a European border and coastguard agency, under a proposal that EU officials hope will be finalized by the end of June. The bloc hopes that better protection of external borders will convince countries within its normally free-travel Schengen area to lift emergency border controls put in place to stem migration flows.
HUMANITARIAN AID: The commission has created a new legal channel to provide the member states worst hit by the migration crisis with 700 million euros in humanitarian aid over three years. The needs are particularly acute in Greece, where an estimated 46,000 migrants and asylum seekers are stranded after borders were closed to them last week along the migration route leading from Greece to Europe's wealthy northern states. EU governments gave their blessing Wednesday for a first disbursement of 100 million euros for Greece and other countries.
MILITARY ACTION: The EU has launched a naval mission to crack down on the criminal networks smuggling migrants across the southern Mediterranean Sea. It can intercept boats and arrest suspected criminals in international waters. The NATO military alliance has also launched an operation to monitor the smuggling networks that help people cross the Aegean Sea from Turkey to Greece. It will only intervene if a vessel is in distress.
MIGRANT RELOCATION: The EU has been trying to implement a contentious emergency scheme for the redistribution of 160,000 asylum seekers from countries on the front lines of the migration crisis - such as Greece and Italy - to other member states. But by March 15, only 937 people had been relocated. Some member states are not keen to take in asylum seekers, who in turn have been reluctant to participate since they cannot choose where to go. This has started to change after the onward route from Greece was closed off last week, EU officials say. The European Commission now wants member states to relocate 6,000 people by mid-April and 20,000 by mid-May. It has also proposed the creation of a permanent relocation system.
MIGRANT RESETTLEMENT: EU member states agreed last year to take in 20,000 displaced people who are outside the EU but in need of international protection, such as Syrians living in UN refugee camps. The commission is expected to propose this year the establishment of a "structured" resettlement system. The new deal being hashed out with Ankara could also see some member states voluntarily take in additional numbers of Syrian asylum seekers out of Turkey.
MIGRANT RETURNS: The EU wants to do a better job at sending back economic migrants who do not qualify for international protection. In the past, only about 40 per cent of such migrants have been returned to their countries of origin. The creation of beefed-up reception centres - known as hotspots - in Greece and Italy is supposed to help in quickly identifying economic migrants and initiating return procedures. The hotspots, which were slow to come online, are also meant to administer relocations.
ORIGIN AND TRANSIT COUNTRIES: The EU has been working to enlist the help of migrants' origin and transit countries to stem the flow heading its way, notably in Africa. It launched a 1.9-billion-euro fund in November to help tackle migration from that continent, but struggled to impress recipient countries, which accused Europe of focusing too much on sending Africans back home.
EU REFORM: The commission is expected in April to launch an attempt to reform the Dublin system, under which asylum claims are supposed to be registered in the first EU country where an asylum seeker sets foot. The system broke down during the migration crisis. The EU's executive is also working on proposals to make it easier for skilled migrants to legally enter the bloc.