Buenos Aires  - Argentine farmers called for renewed dialogue with the government Tuesday, as they extended their latest protest measure until Sunday.

The government in turn stressed that there will be no negotiations in the current setting, since farmers have declined to make concessions in their demands despite several talks since the crisis started in March.

"The government called for dialogue many times. The only one that changed its position was the government, not the farmers. But we trust that at some point everyone will come to reason," Chief of Staff Alberto Fernandez told a Buenos Aires radio station.

Argentine President Cristina Fernandez de Kirchner was in Rome for a UN food summit.

The crisis in one of Argentina's top economic sectors has been brewing since March, when an increase in export tariffs for soybean and sunflower went into effect, tying tariffs to international market prices.

The average tariff was increased from 35 to 41 per cent and amounted to almost all of the surplus if the price for soybeans were to rise above 600 dollars a tonne, although the government has since modified this to set a tax ceiling.

The positions of the government and agricultural producers have remained far apart.

In March, a complete blockade of agricultural production caused severe food shortages in large urban areas and provoked traffic problems. Earlier this month, farmers opted to block the export of cereal and other key products, like soybeans.

In their third protest, farmers again took to the roads last week. Although their leaders asked that they not disturb traffic, the passage of trucks carrying agricultural produce was blocked in some areas.

In a strike that was set to end Monday but was prolonged until the end of the week, farmers were blocking the sale of cereal and oil- based crops for export. They however allowed the sale of cattle for meat from Tuesday, to prevent shortages in the internal market.

Farmers also demand government policy that again makes dairy farming, cattle raising and regional products profitable.

After years of meagre earnings, Argentina's farmers don't want the export duties to cut into their profits just as they have begun to see more money flowing in with higher world food prices.

The halt to agricultural exports has proved expensive for the government because a large part of its income comes from export duties. (dpa)