The United States abstained on a World Bank vote for a loan to Eskom Holdings Limited, South Africa's state-owned power company, because of environmental concerns, the Treasury Department said in a statement in Washington.

Bloomberg reported on Thursday, that Eskom has requested a $3.75bn loan, the bulk of which would be used to help finance one of the world's largest coal- fired power plants, which the utility is building in the northern Limpopo province.

As of 3:15pm in Washington, the World Bank had not communicated on the outcome of its board's meeting.

The US's decision ' reflects concerns about the climate impact of the project and its incompatibility with the World Bank's commitment to be a leader in climate change mitigation and adaptation,' the Treasury said in an e-mailed statement. South Africa, the world's biggest producer of platinum, is suffering from a power shortage that forced shutdowns at mines and factories in 2008's first months. The planned Medupi plant has sparked protests from environmental and civil rights groups on pollution and distribution concerns and raised questions among some US lawmakers.

While recognising South Africa 'faces limited options that could provide the required energy base for South Africa and the region in lieu of the project,' the US has concerns about 'the significant greenhouse gas emissions' it would produce, the Treasury said.

Without measures to offset carbon emissions, 'the project is incompatible with the World Bank's strategy to help countries pursue economic growth and poverty reduction in ways that are environmentally sustainable,' the Treasury's statement said.

The US is the biggest shareholder of the Washington-based World Bank.