The Ex-Im Bank board decision was made after a "careful environmental review" of the 1200MW Thai Binh Two power plant, according to a statement from the Ex-Im Bank sent to Reuters.

The bank was under significant pressure from environmental groups to reject the funding, with a letter from fiver group to the president last week calling the funding “a violation of your Climate Action Plan and the Export Import Bank’s environment policy.”

The groups included Friends of the Earth, Greenpeace USA, Pacific Environment, Center for International Environmental Law, and Center for Biological Diversity.

Friends of the Earth senior strategic adviser Damon Moglen thanked the Obama administration for keeping its promise.

“Friends of the Earth commends the Obama Administration for rejecting financing for this dirty power plant, and believe it bodes well for the implementation of the President’s ban on public financing for overseas coal deals,” Moglen said.

“We urge Ex-Im and other government agencies to ensure that the spirit and intent of this commitment is upheld, and not weakened by fine print and loopholes.

“With this momentum, the president should now encourage these institutions to support investment in renewable energy, efficiency technologies and energy storage so as to assure that we have a real, clean 21st century energy future.”

Ex-Im financing for fossil-fuel projects in countries such as India and South Africa reached a record $9.6 billion in 2012, almost double the 2011 total, according to data compiled by Pacific Environment.