The major border checkpoints of Ilinden-Exochi and Makaza-Nymphaea, connecting Bulgaria and Greece, are closed to all traffic as of 13:00 local time (EET), Bulgarian police authorities have said in a statement.

This includes cars and buses as well as transit commercial trucks.

A blockade of Greece's borders with its neighbors has been in place since the end of January as farmers are protesting against a planned pension reform and other austerity measures Athens has agreed with international lenders.

At Kulata-Promachonas, where the biggest queue has been formed over the past few days with stretches of only a few hours a day when transit trucks can move freely, trucks are able to cross both ways only between 12:00 and 14:00 local time (EET) on Saturday.

The other border crossings between the two countries are open to all traffic, police say.

The information comes amid reports that farmers are planning to intensify the blockades across the country and at the borders as part of their effort to pressure the government of Alexis Tsipras into abandoning the reforms.

Athens has so far put forward the idea to establish a committee bringing together representatives of parties and farmers' unions, according to Kathimerini.

Farmers for their part say they will not withdraw unless the government backtracks on the social security reform.

The newspaper also says that, as of Friday, at the border crossing of Promachonas (on the Greek side of the border) trucks were "backed up almost 30 kilometers).