About 1,000 migrants have left their sprawling camp in northern Greece, trying to find a way through the border fence into Macedonia.
They marched away from the Idomeni camp, and dozens of them then crossed a river near the border.
Greek police later surrounded the group, the AFP news agency said, but there were no reports of any clashes.
Some 14,000 people have been stranded at the camp, where conditions have deteriorated following days of rain.
In other developments on Monday:
- Macedonian police say two men and one woman found drowned in the Suva river on Monday were migrants trying to enter the country from Greece
- The UN refugee agency says 19 migrants have been placed in a shelter in Macedonia and three in hospital after crossing the river, AP reports
‘We can cross’
The migrants – many carrying all their belongings – were seen walking in a long snaking line along a hilly road on Monday. The group included a number of children.
When they reached the river, they passed a rope across it and formed a “human chain” to help each other to get to the other side.
The migrants said they were trying to find a gap in the barbed wire fence on the border.
“We hope we can cross because we are a lot of people. Our number is big now,” 24-year-old Syrian migrant Aziz told APTN.
“We don’t want to stay here [Idomeni] in that camp. Because we are tired of being there,” he added.
There was no immediate sign of Macedonian police across the border, reports said.
Macedonia last week said it would no longer let any migrants in, blocking the so-called Balkan route north.
The move came after the EU and Turkey had set out a plan to ease Europe’s biggest refugee crisis since World War Two.
Under the plan, still to be finalised, all migrants arriving in Greece from Turkey would be sent back. For each Syrian returned, a Syrian in Turkey would be resettled in the EU.
Hundreds of thousands of migrants have travelled through Macedonia over the past year, heading north.
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What’s in the EU-Turkey proposal?
The EU leaders said “bold moves” were needed, and made the following proposals:
- All new irregular migrants crossing from Turkey to Greece will be returned to Turkey. Irregular migrants means all those outside normal transit procedures, ie without documentation
- In exchange for every returned Syrian, one Syrian from Turkey will be resettled in the EU
- Plans to ease access to the EU for Turkish citizens will be speeded up, with a view to allowing visa-free travel by June
- EU payment of €3bn ($3.3bn; £2.2bn) promised in October will be speeded up, with the possibility of further aid to help Turkey deal with the crisis. Turkey reportedly asked for the sum to be doubled
- Preparations will be made for opening new chapters in talks on EU membership for Turkey
A note on terminology: The BBC uses the term migrant to refer to all people on the move who have yet to complete the legal process of claiming asylum. This group includes people fleeing war-torn countries such as Syria, who are likely to be granted refugee status, as well as people who are seeking jobs and better lives, who governments are likely to rule are economic migrants.