Russia calls U.S. allegation it arms Taliban unsubstantiated

MOSCOW (Reuters) - Russian Foreign Minister Sergei Lavrov said on Tuesday that a U.S. allegation Moscow was supplying arms to Taliban insurgents in Afghanistan was unsubstantiated. The head of U.S. and international forces in Afghanistan said on Monday he was "not refuting" reports that Russia was providing support, including weapons, to the Taliban. (Reporting by Maria Kiselyova; Writing by Polina Devitt; Editing by Andrew Osborn)