Iran must give UN nuclear inspectors access to a workshop at the TESA Karaj complex as previously agreed or face diplomatic retaliation, the US warned on Monday after the IAEA said it Tehran was not fully honouring the terms of the recent oversight deal. The workshop makes parts for centrifuges, machines that enrich uranium, and was targeted by apparent sabotage in June in which one of four International Atomic Energy Agency cameras there was destroyed and another badly damaged, after which Iran removed them. TESA Karaj was one of several sites to which Iran agreed to grant IAEA inspectors access to service the UN body's monitoring equipment and replace memory cards just as they were due to fill up with data such as camera footage. The September 12 accord helped avoid a diplomatic escalation between Iran and the West. "We are deeply troubled by Iran's refusal to provide the IAEA with the needed access to service its monitoring equipment, as was agreed in the September 12 Joint Statement between the IAEA and Iran," a US statement to the IAEA's 35-nation Board of Governors on Monday said. It was responding to a report by IAEA Director-General Rafael Grossi on Sunday that said Iran had granted access to sites as agreed on September 12 but not to the workshop where IAEA inspectors were denied access on Sunday. They had planned to check if the workshop was ready to operate and re-install cameras if it was. "We call on Iran to provide the IAEA with needed access without further delay," the US statement said. "If Iran fails to do so, we will be closely consulting with other board members in the coming days on an appropriate response." The UN watchdog on Sunday warned that Iran was not fully honouring the terms of the September 12 agreement. "The director general [Rafael Grossi] stresses that Iran's decision not to allow the agency access to the Tesa Karaj centrifuge component manufacturing workshop is contrary to the agreed terms of the joint statement issued on September 12," the International Atomic Energy Agency said. Iran's envoy to IAEA said on Monday that the director general's report wasn't accurate and goes beyond the agreed terms of the joint statement. He said that as the Tessa Karaj Complex was still under "security and judicial investigations" after the apparent sabotage in June, the equipment there was not included in the September deal. "Any decision taken by Iran on monitoring equipment is only based on political rather than legal considerations and the Agency cannot and should not consider it as one of its entitlements," Kazem Gharibabadi said on Twitter. A resolution by the IAEA Board of Governors could have killed hopes of resuming wider talks on reviving the Iran nuclear deal. Iran's new, hardline President, Ebrahim Raisi, has said it is prepared to return to the nuclear negotiating table but not under western "pressure".