Greece's government was on Tuesday scrambling to keep angry farmers from blocking key infrastructure after airports were occupied on Crete in a growing nationwide protest for agriculture funds.

Thousands of tractors have intermittently blocked highways and border crossings since late November, and the farmers have vowed to block the central port of Volos on Wednesday.

"At this moment, there are over 20,000 tractors on the roads of Greece, possibly approaching 25,000," Sokratis Alifteiras, a senior farm unionist for the central Larissa region, told AFP.

"The decision made by the farmers of Thessaly for tomorrow morning is to block the port of Volos" from both land and sea, he said.

The conservative government of Kyriakos Mitsotakis has for months struggled to address a farm subsidy scan

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