Bolivia's President Evo Morales has urged Congress to back his plan for an "agrarian revolution" to correct a "historical injustice".
Unequal land distribution is at the root of Bolivia's problems, says Morales
Mr Morales was speaking at a ceremony in central Bolivia, where he handed out 2,300 land titles and 50 new tractors.
Mr Morales's government has handed out a substantial area of state-owned land already, but is seeking the right to expropriate unproductive private land.
However these plans have been fiercely opposed by landowners.
Mr Morales made his remarks during the ceremony in Urucena, a town in the central department of Cochabamba, where in 1953 the first agrarian reform was launched in Bolivia.
The principle objective of the government was, he said, "to expropriate unproductive land, which performs no social or economic function" and give it to those without land.
"If in Bolivia we do not resolve the social and economic problems of the indigenous and peasant communities we will never be able to resolve the economic problems of the nation, and for this reason we have the obligation to change the politics of the land," he said, according to the news agency Efe.
Mr Morales, himself an Aymara Indian, referred to the "historical injustice" of the Spanish conquest of Bolivia 500 years ago.
Mr Morales arrived at the ceremony on a tractor, leading a convoy of 50 Venezuelan-made tractors which were distributed to agricultural workers.
The Senate has so far failed to allow private lands to be seized
He promised hundreds more tractors would be distributed to Bolivia's impoverished peasants - some of whom still use ox-driven ploughs to furrow the fields.
At the ceremony - attended by some 20,000 supporters - he also handed out some 2,300 new land titles.
The total area of land handed out on this occasion was not reported, but the government is said to have distributed 24,800 sq km (9,600 sq miles) since the agrarian reform programme started in June.
At present Mr Morales is restricted to handing out state-owned land, and so far Congress has failed to back plans to redistribute privately owned land which is unproductive, obtained illegally or used for speculation.
On Wednesday, Mr Morales suggested he might bypass Senate opposition through presidential decree or a change in the constitution.
Mr Morales has vowed to redistribute 200,000 sq km - an area double the size of Portugal - by the end of his term in 2011.
But the programme has enraged landowners, with Bolivia's main landowners' federation pledging to form "self-defence groups" to defend their land.
One landowners' group has called the plan "a nuclear bomb for Bolivian agriculture".