Europe's external borders must be protected even more tightly to stop the flow of migrants on the Balkan route for good, leaders from the region agreed at an informal summit in Vienna on Saturday.
Although Balkan countries and Austria closed down the route in mid-February, 50,000 people have managed to reach Germany since then, Austrian Chancellor Christian Kern said, citing his German colleague Angela Merkel.
"We need to regain control over our external programme, we need to be the ones who decide who comes to Europe, and not smuggler organizations," Kern told reporters after the meeting that included Merkel, top EU officials as well as premiers from Balkan countries and Greece.
Leaders discussed a possible expansion of the EU's Frontex border control mission in the region, but Kern indicated there was no complete agreement on this issue when he said that the participants "had tried to reach a commitment."
In addition, the heads of government talked about helping Greece to speed up its asylum procedures to reduce the number of people who end up travelling on to Western Europe rather than waiting for Greek bureaucracy.
Austria, Germany and EU institutions would also work with Greece so that it accepts Turkey as a safe country for migrants, which would allow Greece to send back Afghan and Pakistani refugees to Turkey, Kern added.
Regarding the migrants' home countries, leaders said they would push the European Commission, the EU executive body, to intensify efforts on repatriation agreements with Niger, Mali, Senegal and Egypt, modelled on the existing deal with Turkey.
Talks on an EU-Afghanistan deal looked promising, he said.
"Our aim must be to stop illegal migration as much as possible," Merkel told reporters.
Germany had agreed to take in several hundred migrants per month from the main arrival countries Italy and Greece, she added.
The Vienna summit had resulted in work assignments not only for the commission, but also for EU member states to commit personnel to Frontex, Kern said.
"The only way how we can make progress and move to the right direction on this is by increasing pressure, increasing more pressure and increasing yet more pressure," he said.
EU countries would only agree to relieve Greece and Italy by taking in asylum seekers once the external borders are secured, Kern stressed.
Greece has asked Frontex to secure its borders with Macedonia and Albania, the EU agency's director Fabrice Leggeri was quoted as saying by the Sunday edition of the German newspaper Die Welt.
"We have been holding good talks with Athens about the concrete design of this mission," he said.
In February, regional countries decided to close the Balkan route.
Greece and Germany, which were not part of this decision, were irritated. Migrants were left stranded in Greece, while Berlin warned that border closures were not the answer to the migration crisis.
However, this step along with the EU-Turkey deal and Hungary's restrictive policies have reduced arrivals in major refugee destination countries like Germany, where Merkel faces criticism from friends and foes over her open-door policy.
The European Union had also been critical of the Balkan countries' initiative, but on Saturday European Council President Donald Tusk said EU member states must work closely with Balkan countries and Turkey to stop the inflow.
"We need to confirm politically and in practice that the Western Balkan route of irregular migration is closed for good," he said.
At the same time, European Migration Commissioner Dimitris Avramopoulos criticized EU members who have refused to take in asylum seekers.
"Solidarity is not a la carte," he said, in a veiled reference to eastern EU countries.
Besides Austria, Germany and Greece, the Vienna meeting includes leaders from Macedonia, Serbia, Albania, Croatia, Slovenia, Bulgaria, Romania, and Hungary.