Macedonian police have fired tear gas to disperse around 50 migrants stranded in Greece who tried to pull down part of the razor wire fence separating the two countries.
Scuffles briefly broke out and Greek riot police later intervened to break up the crowd.
Greek authorities say Macedonian police fired tear gas and stun grenades to deter the group from trying to get over the razor-wire fence using blankets.
No injuries were reported from Wednesday's clashes.
Tensions have boiled over in recent days at the makeshift migrant camp near the town of Idomeni, where more than 10,000 migrants and refugees have been stranded since February, when Balkan countries shut their borders to anyone wanting to head north.
Hundreds of migrants were wounded on Sunday in clashes with Macedonian police, who fired tear gas and rubber bullets after a group tried to storm the border.
The Balkan route was the preferred gateway into western and northern Europe last year for around 1 million migrants from the Middle East and beyond.
