Thousands of people have taken to the streets of Buenos Aires to show their support for Argentina's president, who is embroiled in a dispute with farmers. ( BBC )
Farm workers have been on strike for three weeks, blockading roads in protest at tax increases on soya.
President Cristina Fernandez says the export tax rises will help curb fast-rising domestic food prices.
The farmers' disruption has caused acute shortages of meat, milk and fresh produce across Argentina.
Tuesday's march in favour of the measures brought together union members, community groups and human rights activists who walked through the streets of the capital waving banners.
Ms Fernandez addressed the rally, calling on farmers to end their 20-day strike, which has blocked motorways and prevented farm goods reaching the capital.
"Don't do more harm to the people, lift the roadblocks so Argentines can get food," she said.
Ms Fernandez has said the higher taxes on soy exports will help control rising inflation on domestic food goods.
The government has also been using taxes on grain and commodity exports to boost state revenues.
But trade at Argentina's largest grain and cattle markets has ground to a halt while many shops are reporting shortages of supplies of beef and chicken, diary goods and fruit and vegetables.
The march comes a week after thousands of middle-class Argentines banged pots and pans along the capital's streets in support of the farmers' protest.
Argentina is one of the world's top exporters of soya, wheat and beef and any prolonged conflict will have a major effect on vital export earnings, says the BBC's Daniel Schweimler in Buenos Aires.
The farmers' strike is the biggest crisis faced by Ms Fernandez since she took office more than three months ago, succeeding her husband Nestor Kirchner, our correspondent adds.