Iran and the UN nuclear watchdog agreed Sunday on new "practical" steps to increase transparency over Tehran's controversial nuclear work, although a suspect military site remained off-limits.
Iranian officials said the International Atomic Energy Agency was not being granted access to the Parchin military site, where Tehran is suspected of having experimented with nuclear arms development.
Talks in Tehran between Iran and the IAEA on Saturday and Sunday also did not cover allegations that prior to 2003, and possibly since, Iran's nuclear work had "possible military dimensions", state media said.
The encounter, building on a roadmap agreement reached in November, led to agreement on "seven more practical steps in regards to cooperation with the agency," said Iran's envoy to the Vienna-based body, Reza Najafi.
He said the measures -- including managed visits to a uranium extraction mine and a yellowcake facility -- must be implemented by May 15.
IAEA director general Yukiya Amano is expected to brief the agency's broad of governors on the agreement's details.
ISNA news agency, citing an unnamed member of Iran's negotiating team, said they included "managed visits to the (uranium extraction) mine in Saghand and the yellowcake facility in Ardakan," where an impure state of uranium oxide is prepared to be fed into centrifuges for enrichment.
The plant in Ardakan, officially unveiled in April 2013, receives raw material from Saghand mine, some 120 kilometres (75 miles) away. It can reportedly produce up to 60 tonnes of yellowcake annually.
The ISNA report did not give dates for visits to the sites, but added that other parts of the deal entailed "divulging information and explanation regarding some remaining issues."
Describing the talks, Najafi said "constructive technical meetings" had assessed "the progress in implementation of practical steps" required of Iran under the framework deal agreed in November.
The deal required Tehran to take six practical steps that included a visit to the unfinished site of a so-called heavy water research reactor in Arak, where Iran is struggling with a series of delays in its construction.
The Arak reactor is of international concern because it could theoretically provide Iran with a second route to a nuclear bomb -- an alternative to highly enriched uranium -- through extraction of weapons-grade plutonium from spent fuel if it also builds a reprocessing facility.
Iran's enrichment activities are in defiance of repeated UN Security Council demands and resolutions, amid suspicions in the West and Israel that Tehran's nuclear drive masks military objectives, a claim it has repeatedly denied.
A sore issue in long-running discussions between Iran and the IAEA has been the Parchin military site near Tehran, where the agency suspects explosive tests took place that are "strong indicators of possible nuclear weapon development".
Iran says it has no obligation to grant the IAEA access to the site, arguing that Parchin's designation as a military site puts it off-limits to inspections.
After the talks in Tehran, Iran's Atomic Energy Organisation spokesman Behrouz Kamalvandi said a visit to Parchin was still not included in the new seven-step deal.
"Visiting Parchin is not included in the seven steps," he said.
The IAEA says it needs to examine the site, pointing to new information it has uncovered since its last visits in 2005
Six world powers negotiating with Iran on its current nuclear activities called on Tehran in March 2012 to allow IAEA inspectors to visit the site.
Parchin, near Tehran, is not a nuclear-declared site so it is not subject to IAEA inspections.
Amano had raised expectations last month that alleged weaponisation studies would be broached in future talks with Iran after he told AFP last month that the time was ripe to ask "more difficult" questions.
How long this takes "very much depends on Iran. It can be quick or it can be long. It really depends on their cooperation," Amano said.