A senior official of the United Nations nuclear supervisory body the International Atomic Energy Agency (IAEA) said that Wednesday talks in Iran had ended inconclusively and international inspectors had not been given access to a site that they suspect may have been used for testing bomb triggers.

Once again, inspectors were denied access to Parchin, the military site 20 miles south of Tehran that inspectors want to examine for evidence of bomb trigger tests. While Western powers suspect Iran is seeking nuclear weapons technology, Tehran says its program is for civilian purposes.

On a separate negotiating track, Iranian officials are scheduled to meet in Kazakhstan this month with representatives of the P5+1— the United States, China, Russia, Britain, France and Germany — for the next round in a long-running series of talks about curbing Iran’s uranium enrichment program. So far those talks have also been inconclusive.