UN nuclear watchdog officials will visit Iran in the coming days, Tehran’s nuclear chief Mohammad Eslami said on Wednesday, to try to end an impasse over traces of uranium found at Iranian undeclared sites.

“We hope the visit of the International Atomic Energy officials to Tehran in the coming days can help resolving issues with the agency,” Eslami told state TV.

The issue has been an obstacle to progress in wider talks to revive the 2015 Iran nuclear deal with major powers to curb its disputed uranium enrichment program in return for lifting sanctions imposed by Washington after exiting the pact in 2018.