U.N. nuclear watchdog says pace of Iran's cooperation slow

International Atomic Energy Agency (IAEA) Director General Yukiya Amano waits for the start of a board of governors meeting at the IAEA headquarters in Vienna March 2, 2015. REUTERS/Heinz-Peter Bader

VIENNA (Reuters) - The U.N. nuclear watchdog chief said on Monday Iran was being slow to cooperate with his agency's investigation into the Iranian atomic programme and that the inquiry could not continue indefinitely.

Diplomats have voiced doubt over whether the outstanding issues in the U.N. investigation would be resolved before a broader diplomatic agreement is reached between Iran and the United States, Britain, France, China, Russia and Germany.