Iran rejects voluntary inspections amid nuclear deal standoff
The head of the International Atomic Energy Agency (IAEA) on Monday asked Iran to ensure "timely and proactive cooperation", with Tehran, for example, inviting inspectors to visit sites they have not specifically demanded to see.
However Tehran's ambassador to the IAEA, Reza Najafi, on Wednesday said that while the country was not benefiting from the deal, "no one should expect Iran to go to implement more voluntary measures".
The nuclear accord struck under former US President Barack Obama lifted economic sanctions against Iran in return for curbing its nuclear programme.
Now sanctions have been reimposed by Obama's successor, President Donald Trump, who announced the US withdrawal from the pact in May.
Meanwhile European signatories to the deal are struggling to keep it afloat, with France warning Iran against moving ahead with its plans to ramp up uranium enrichment.
Officials in London, Paris and Berlin also on Wednesday sent a request to the US to exempt their companies from punitive measures resulting from new sanctions on Iran.
Najafi would not be drawn on how much longer talks between the Europeans and Iran on salvaging the deal would last.
"We gave a few weeks to our European counterparts," he told reporters outside a quarterly meeting of the agency's Board of Governors. "A few weeks means a few weeks, not a few months."