Morales, a former coca-farmers' leader and ally of Venezuelan President Hugo Chavez, swept to victory in December on promises to give Bolivia's poor a greater share of the wealth created by the country's natural resources. On May 1, he seized the assets of foreign oil companies, raised taxes on natural gas and forced companies to renegotiate contracts.

The accord will help supply the northeast region of Argentina, Kirchner said in a televised speech from Bolivia, where he traveled earlier today to sign the agreement with Morales. Details of the accord weren't provided.

``This accord is a strategic and fundamental step,'' Kirchner said. ``Thanks to this accord, Argentines in the northern region who don't have gas will be supplied by a pipeline.''

Argentina needs to increase its natural gas imports to power thermoelectric generation plants that have had shortages due to a rise in electricity demand as the economy expands for a fourth consecutive year. The governments agreed to boost natural gas imports from Bolivia to 27 million cubic meters per day during the next 20 years from 7 million cubic meters, according to the Presidential palace official Web site.

``Social and economic problems force us to join together, and here we are united because of energy problems,'' Morales said at the signing ceremony.

Under the terms of the accord, Bolivia will gradually increase its natural gas exports to Argentina to reach 27.7 million of cubic meters by 2010, Bolivia's state news agency said, citing Juan Carlos Ortiz, president of Yacimientos Petroliferos Fiscales Bolivianos.