The European Council president has warned refugees against coming to Europe for economic benefit as thousands of people remained trapped at the Greece-Macedonia border after being blocked from continuing their journey.
"I want to appeal to all potential illegal economic migrants, wherever you are from: Do not come to Europe," Donald Tusk said in Athens on Thursday after meeting Greek Prime Minister Alexis Tsipras.
"Do not risk your lives and your money. It is all for nothing. Greece, or any other European country, will no longer be a transit country."
Greece is the first transit point for refugees seeking to make the journey north to more prosperous EU states.
The vast majority of the people arriving in Greece are those fleeing war and political repression in countries such as Syria, Iraq, and Afghanistan.
But EU politicians have sought to crack down on those they say are motivated by financial betterment.
Tusk was on a trip through Balkan states to try to drum up support for cohesion on how to deal with hundreds of thousands of refugees - a crisis that threatens to tear the bloc apart - ahead of an emergency EU-Turkey summit on the ongoing crisis on Monday.
His comments came as a bottleneck of refugees had formed at Idomeni, near the Greek border with Macedonia, after Skopje severely curbed the number of people allowed to cross into its territory.
Thousands continue to enter Greece every day but are finding their route north blocked by Macedonian security forces, who are conducting vigorous checks on the refugees who manage to reach their checkpoints.
At least 10,000 people, including women and children, are stuck outside the crossing at Idomeni with little access to basic provisions.
Al Jazeera's Hoda Abdel-Hamid, reporting from Idomeni, said the situation at the border was getting "worse by the day.
"This is a makeshift camp. The transit camp is already at full capacity so people are setting up their tents wherever they can. 
"They're going to the woods to set up fires when the temperatures fall dramatically ... people are frustrated with each day that passes, they're getting more and more tired.
"There's a very very long queue in front of the [Greek] police desk made up of people waiting for hours on end to get the right stamp."

Fair share

The number of refugees flowing into Europe has soared in the first two months of 2016 amid tighter borders and ongoing conflicts in the Middle East, prompting warnings from agencies and rights groups of a "looming humanitarian crisis".
On Tuesday, the UN's refugee agency, the UNHCR, said that 131,724 people made the journey across the Mediterranean during January and February, with 122,637 refugees landing in Greece.

READ MORE: Crisis looms as a new wave of refugees reaches Europe

After his meeting with Tusk, Tsipras lashed out at fellow EU leaders for not taking their fair share of refugees and forcing Athens to deal with the huge numbers waiting to cross through.
The Greek leader called for sanctions on EU states that refuse to accept refugees.
"At Monday's summit, Greece will demand that burden-sharing be equitable among all countries in the bloc, and sanctions for those that do not," Tsipras said.
"We ask that unilateral actions stop in Europe," he added, in a view echoed by Tusk.
Tusk later travelled to Turkey, which has taken more Syrian refugees than any other country, and is the departure point for the majority trying to reach the EU.