Farmers protesting the government's increases to tax and social security contribution payments on Friday kept their tractors parked at the Nikaia junction on the national highway linking Athens and Thessaloniki.
The action prompted traffic police to divert traffic in the broader region. There were also road blockades in Achaia, in the Peloponnese, and in Arta.
The farmers on Friday threatened to block the border crossing at Promachonas, near the Bulgarian border, as they did last year, causing serious cross-border transport problems and diplomatic tensions with Sofia, unless the government makes concessions.
On Thursday, farmers from Serres tried to approach the border but were obstructed by police at Sidirokastro.
Unionists are due to meet on Friday afternoon in several cities in central and northern Greece to decide on their further course of action.