European Council President Donald Tusk has criticized EU member states for taking unilateral action to block their borders to migrants and refugees.
He also has issued a warning that economic migrants should not come to Europe.
Tusk made the remarks at a press conference in Athens on March 3 after talks with Greek Prime Minister Alexis Tsipras.
Tusk said: "I want to appeal to all potential illegal economic migrants wherever you are from: Do not come to Europe. Do not believe the smugglers. Do not risk your lives and your money. It is all for nothing."
Tusk also attacked actions by individual European states that he said "erode trust" by dividing the EU.
Tusk said: "Unilateral decisions without prior coordination" were "detrimental to the European spirit of solidarity."
Austria's restrictions on migrants has led to a domino effect of border closures along the so-called Balkan route for migrants in Slovenia, Croatia, and non-EU members Macedonia and Serbia.
The clampdown has stranded in Greece some 24,000 migrants who are trying to reach more prosperous countries in northern Europe.