"We call on our Iranian colleagues to show sangfroid, not to give in to emotions by any means and observe key provisions of the IAEA Safeguards Agreement and the Additional Protocol to this agreement," Russian Foreign Minister Sergei Lavrov said.

He said that Russia would do everything to help preserve the Iran nuclear accord.

"This agreement has special significance for the strengthening of the (nuclear) non-proliferation regime," Lavrov said, speaking after talks with Irish Foreign Minister Simon Coveney.

But all parties -- not just Tehran -- have to honour their commitments for the Iran nuclear agreement to be preserved, Lavrov added.

"I would very much want our European colleagues to understand the full measure of their responsibility for preserving the Joint Comprehensive Plan of Action," Lavrov said.

European countries should "safeguard Iran's economic interests" and help it sell its oil, Russia's top diplomat said.

Instex, a mechanism that Germany, France and Britain said they would create to help Iran bypass US sanctions, has yet to materialise, Lavrov said.

Iran announced in May that it would no longer respect the limit set on its enriched uranium and heavy water stockpiles.

The move was seen as a way of exerting pressure on Europe to try and salvage the deal which has been hanging by a thread since US President Donald Trump announced that he was withdrawing from the accord and reimposing biting sanctions on Tehran.

On Monday, Foreign Minister Mohammad Javad Zarif said Iran had now exceeded the limit on its enriched uranium reserves.