UPDATE 1-OYU Tolgoi copper mine agreement reached, Rio Tinto says
May 18, 2015 at 18:43 PM EDT
SYDNEY, May 19 (Reuters) - An agreement to develop the OYU Tolgoi copper mine in Mongolia has been reached, Rio Tinto said on Tuesday, ending a two-year hiatus that saw the underground project delayed amid disputes over costs and taxes after the open pit mine was built.