Farmers are threatening a return to the blockades and protests
Hundreds of thousands of people in Argentina have attended rival rallies by farmers and the government, in a dispute over higher taxes on exports.
The farmers - who are profiting from high global commodity prices - say a new regime of taxes, export limits and price caps on their produce is unfair.
But President Cristina Fernandez de Kirchner told a rally her policies were aimed at redistributing wealth to all.
The ongoing row, including two strikes, has led to a shortage of produce.
The two rallies coincided with the Revolution Day public holiday - when the country unites to mark the founding in 1810 of the movement that led to its independence from Spain.
But instead, there was a deep split as tens of thousands of farmers and their supporters gathered in the city of Rosario to call on the government to lower export taxes.
Farmers on tractors filled the main square, where they waved national flags and listened to music celebrating rural life before the main farm leaders spoke.
In March, a three-week farmers strike led to food shortages across the country.
President Fernandez is facing her biggest test since taking office
"We must be prepared to return to the blockades and protests, to take the necessary decisions if there's no change soon to the restrictions," said Eduardo Buzzi, president of the Argentine Agrarian Federation.
"We are going to be very firm. This is a struggle that has only one end: to win," he said.
The government of Cristina Fernandez de Kirchner says it will not back down and that the taxes, mostly on soya exports, are necessary to redistribute wealth and help fight poverty.
At a separate rally in the northern city of Salta, the president said that "before any sector, before our own individuality, come the interests of the country".
Talks between the two sides are due to resume on Monday. But the BBC's correspondent in Buenos Aires, Daniel Schweimler, says they do not promise much.
Argentina is one of the world's leading producers of soya, wheat and beef and our correspondent says a continued dispute will have an increasing impact on world food prices while at the same time plunging President Fernandez's government into deeper crisis.