Iran has been urged to join a nuclear safety convention as it prepares to bring its first nuclear plant into operation.
The International Atomic Energy Agency (IAEA) wants the Middle East country to join the 72-nation 1996 Convention on Nuclear Safety, designed to boost safeguards after the 1986 Chernobyl disaster.
The issue that has gained fresh urgency following Japan's Fukushima nuclear crisis this year, through a system of peer review and mutual oversight.
Iran would be the only country operating a nuclear power plant not to belong to the convention, warned Denis Flory, deputy director general of the International Atomic Energy Agency (IAEA).
"Our first wish would be that all IAEA member states operating nuclear power plants in the world are parties to the convention on nuclear safety," Flory said.
Final tests are being conducted at the Bushehr plant, the first of a network of nuclear power stations Iran is planning, which has missed deadline after deadline to come on-stream due to technical problems.
A senior Russian official said that Bushehr would be fully operational within weeks, and it is expected to start generating electricity in the next two months.
Iran could demonstrate its commitment to safety by signing up to the global convention, Flory said as western officials called on the country to join the pact.
Iran is embroiled in a long-running dispute with Western powers over its nuclear programme and its ties with the IAEA have also become strained.
Iran's envoy to the IAEA, Ambassador Ali Asghar Soltanieh, said last week that the country was "showing maximum vigilance" about safety.
He also suggested the U.N. agency was already involved, telling a public debate that "every safety matter is monitored" by the Vienna-based body.
However Flory said IAEA member states were responsible for safety and the agency had no such role at Bushehr.
"We do not monitor Bushehr, no more than we monitor any other nuclear plant in the world," he said.
"We do not have ground to state that they follow all IAEA safety standards."
The IAEA has no powers to enforce its safety recommendations - unlike its authority to curb any atomic arms proliferation, where it takes the lead role in monitoring countries like Iran that some Western countries accuse of seeking a nuclear bomb.
"More weight" should be given to IAEA safety standards to help rebuild confidence in nuclear energy around the world after the Fukushima emergency, Flory said.
Think-tank the International Institute for Strategic Studies said in a report after the Fukushima accident that Bushehr's location on the Gulf coast made the safety of Iran's nuclear programme a "regional security concern".
It noted that Bushehr, like Fukushima, is in an earthquake zone.
But Iran does not need to fear a tsunami of the size that knocked out the electricity and back-up cooling systems at Fukushima, as Bushehr is not located by an ocean.