Venezuelan President Hugo Chavez has pledged to help build a natural gas pipeline stretching from Venezuela to Argentina during talks with Argentine leader Nestor Kirchner.
Venezuela has proposed a network of pipelines to carry its natural gas to South American markets and eventually tap into supplies in Bolivia, the continent's second-largest source after Venezuela.
Mr Chavez said he was certain Brazil, Uruguay, Paraguay and Bolivia would participate in the project to guarantee energy "to all of South America for the next 200 years".
The cost for a pipeline running south from Venezuela through Brazil to Argentina has been estimated at $10 billion.
Mr Chavez, a critic of the United States and close ally of Cuba's Fidel Castro, has sought to build strong ties with left-leaning leaders across Latin America, including Mr Kirchner.
Venezuela, the world's Number 5 oil exporter, pledged to supply Argentina with five million barrels of diesel a year to help fuel its tractors and public buses, officials said.
The two leaders also discussed plans for Venezuela to join South America's Mercosur trade bloc.
Chavez says the trade bloc represents an alternative to the US proposal for a hemisphere-wide free-trade zone, which has been criticised by Mr Kirchner and other Mercosur leaders.
AP