WASHINGTON (Reuters) - The United States has made a $500 million grant to the Green Climate Fund, meant to help developing nations combat climate change, the State Department said on Tuesday.

The move, coming days before U.S. President Barack Obama hands over power to Donald Trump, was "long-planned," State Department spokesman John Kirby said in a news briefing.

(Reporting by Yeganeh Torbati; Editing by Alan Crosby)