Athens  - Nearly 2,000 protesting farmers from Crete called off their two-day standoff with riot police at Greece's main port of Piraeus Tuesday and boarded ships to return home.

The farmers from the Greek island had arrived at Piraeus on Monday with scores of tractors and farm vehicles to highlight low commodity prices and demand fresh subsidies - echoing similar protests by farmers on mainland Greece.

On Monday, police fired tear gas to prevent demonstrators from taking their tractors and farm vehicles through Athens to the Ministry of Development.

Farmers, many dressed in traditional black shirts and carrying mountain canes, could be seen hurling tomatoes and potatoes at riot police, who sprayed tear gas into the crowds.

Large parts of Greece's busiest harbour were closed off to traffic owing to the clashes.

Deputy finance and agriculture ministers had met with farmers late on Monday in an effort to convince them to return home, but failed to reach agreement.

Greek farmers have been protesting for the past two weeks over low prices for their products and are demanding financial help from the country's conservative government.

They have used their tractors to block major highways across the country, and have prevented imports and exports across many of the country's northern borders, particularly with Bulgaria.

Many of the roadblocks were lifted after farmers accepted a 500- million-euro emergency aid package from the government - which has yet to be approved by the European Union. (dpa)