Officials from Venezuela and Massachusetts have signed a deal to provide cheap heating oil to low-income homes in the US state.
The fuel will be sold at about 40% below market prices to thousands of homes over the winter months.
Local congressman William Delahunt described the deal as "an expression of humanitarianism at its very best".
Venezuela's President Hugo Chavez is one of the Bush administration's biggest adversaries in Latin America.
He first announced his plan to provide cheap heating oil directly to lower-income Americans while visiting Cuba in August.
The deal involves shipping some 45m litres of heating oil from Venezuela to Massachusetts at a discounted rate via Citgo Petroleum, a US-based subsidiary of the Venezuelan state-owned oil company.
At a signing ceremony in Massachusetts, Mr Delahunt - a Democrat who helped broker the deal - rejected suggestions that it was politically motivated.