Farmers are outraged at the government's decision to reduce agricultural subsidies according to the size of cultivated land, RTV broadcaster said.
Protest leader Miroslav Kis was quoted as saying that farmers from all areas of Serbia had been trying to come to Belgrade by tractor but the police had prevented them from leaving their villages.
We demand the implementation of all measures that were promised to us last autumn, he said, adding that the disgruntled farmers could no longer wait for change.
Some of the protesters managed to skirt the police roadblocks and were heading to Belgrade.