The IAEA, accustomed to long, drawn-out inspections, seems to have lost its patience.
IAEA chief Yukiya Amano said in the statement: “We engaged in a constructive spirit, but no agreement was reached.”
The lack of results of the latest effort mirrored those of an earlier visit by IAEA inspectors a few weeks ago.
But the IAEA has new information about a containment vessel built at the site for explosions tests.
The Iranians have not yet agreed to any of the key IAEA demands for the upcoming visit.
Iran has for years delayed, and sometimes obstructed, in supplying the IAEA with such information at other sites.
“I would caution everyone away from saying the IAEA hack was a just a bunch of kids,” he said.
The IAEA's drawing a line and sticking to it is new in its dealings with Iran.
But the news from the International Atomic Energy Agency (IAEA) was not all bad.
Iranian parliament speaker Ali Larijani warned that Iran could reduce its cooperation with the IAEA.