Months of indirect talks between Tehran and Washington to salvage the nuclear accord with six major powers have stalled since September 2022, with both sides accusing each other of making unreasonable demands.
Ayatollah Ali Khamenei's guarded approval comes days after both Tehran and Washington denied a report that they were nearing an interim deal under which Tehran would curb its nuclear program in return for sanctions relief.
"There is nothing wrong with the agreement (with the West), but the infrastructure of our nuclear industry should not be touched," Khamenei said, according to state media.
The 2015 agreement limited Iran’s uranium enrichment activity to make it harder for Tehran to develop nuclear arms, in return for lifting international sanctions.
In 2018, the then US President Donald Trump exited the pact and re-imposed sanctions that have crippled Iran's economy, leading Tehran to gradually move well beyond the deal's nuclear restrictions and reviving US, European and Israeli fears that Iran may seek an atomic bomb.
Echoing Iran's official stance for years, Khamenei said the Islamic Republic has never sought to build a nuclear bomb.
"Accusations about Tehran seeking nuclear weapons are a lie and they know it. We do not want nuclear arms because of our religious beliefs. Otherwise they (the West) would not have been able to stop it," said Khamenei.
Khamenei, who has the last say on all state matters such as Iran's nuclear program, said the country's nuclear authorities should continue working with the UN nuclear watchdog "under the framework of safeguards".
Under the law, Tehran would suspend IAEA inspections of its nuclear sites and step up uranium enrichment if sanctions are not lifted.
"This is a good law ... which must be respected and not violated in providing access and information (to the IAEA)," Khamenei said.
Last month, the International Atomic Energy Agency reported limited progress over disputed issues with Iran, including re-installing some monitoring equipment originally put in place under the 2015 pact that Tehran ordered removal last year.
