'Whoever starts a war with Iran will not be the one to finish it' – Zarif

German Foreign Minister Heiko Maas said on Monday it was in Iran's "political and strategic interest" to stay in the 2015 nuclear deal, as Tehran warned US against the "economic war" and the UN atomic watchdog voiced concern at increased tensions.

Maas, on a visit to Tehran, insisted that the deal – which has been hanging in the balance since the United States unilaterally withdrew from it last year – was "extraordinarily important" for Europe.

But a defiant Iran's Foreign Minister Javad Zarif warned the US that it "cannot expect to stay safe."

"Mr. Trump himself has announced that the US has launched an economic war against Iran," Zarif said. "The only solution for reducing tensions in this region is stopping that economic war."

Zarif also warned: "Whoever starts a war with us will not be the one who finishes it."

TRT World's Reagan Des Vignes has more.

Iran signed the landmark accord with China, Russia, Germany, Britain, France, and the United States, leading to sanctions relief in exchange for Tehran curbing its nuclear programme.

But the US administration of President Donald Trump has imposed sweeping sanctions on Iran after walking away from the deal formally known as the Joint Comprehensive Plan of Action (JCPOA).

On May 8, Iran retaliated by saying it no longer considered itself bound to keep to the limits of stocks of heavy water and enriched uranium that were agreed as part of the deal.

Iran has also blamed the Europeans for not living up to their commitments.

And it warned that it would stop by early July abiding by restrictions on the level to which it can enrich uranium and on modifications to its Arak heavy-water reactor unless other parties to the JCPOA speed up work on mitigating the effects of US sanctions.

'We have a common goal'

Maas met Iranian Foreign Minister Zarif in Tehran to discuss the future of the nuclear deal.

"We had a serious, frank and rather long discussion," Zarif told reporters at a joint news conference after talks with Maas.

"Together with Germany and the European Union, we have a common goal: to maintain [the nuclear agreement], put an end to tensions and conflicts in the region and [allow] the Iranian people to economically benefit [from this agreement]," he said.

Ahead of meeting Zarif, the German foreign minister acknowledged that the economic benefits Tehran hoped for from the deal were now "more difficult to obtain" but urged Iran to fully respect the agreement.

It is in Iran's "political and strategic interest to maintain this agreement and the dialogue with Europe," he said.

TRT World spoke with Adnan Tabatabai, CEO of the Centre for Applied Research in Partnership with the Orient, for more insights.

'Extraordinarily important'

The nuclear deal, he said, is "extraordinarily important" for Europe's security.

"We do not want Iran to have nuclear weapons," Maas said.

According to Maas, Germany and its European partners "have made the greatest effort to meet [their] commitments."

But Iran thinks otherwise.

"What the Europeans must do, and have done has so far, has not satisfied" our interests, Iran foreign ministry spokesman Abbas Mousavi told a news conference on Monday.

"What we expected from the European Union was that they act on their commitments, but they did not want to or could not," he added.

The US sanctions reimposed last year targeted crucial parts of Iran's economy, namely the oil and banking sector.

The oil embargo has hurt Iran's main supply of foreign revenues, while the banking sanctions scared away foreign investments and made money transfers near impossible for Iranian businesses through official channels.

Europe tried to respond to the US withdrawal by setting up a special trade mechanism called INSTEX that would allow legitimate trade with Iran to continue without falling foul of US sanctions.

Although launched in January, INSTEX is still not operational and has been criticised by Iranian leaders.

IAEA concerned 

Iran has given Europe, China and Russia until July "to make their commitments operational."

Otherwise, Tehran said it will stop complying with the nuclear deal's uranium enrichment restrictions and resume building a heavy-water reactor at Arak that was shut down as part of the deal.

This has sparked concern at the UN's nuclear watchdog which on Monday urged dialogue.

"I ... hope that ways can be found to reduce current tensions through dialogue," International Atomic Energy Agency director general Yukiya Amano told the agency's quarterly board of governors meeting.

"As I have constantly emphasised, the nuclear-related commitments entered into by Iran under the JCPOA represent a significant gain for nuclear verification," Amano said.

"It is essential that Iran fully implements its nuclear-related commitments under the JCPOA," he added.

Two weeks ago, the latest inspections report by the IAEA said that while stocks of uranium and heavy water had increased, they were still within the limits set by the JCPOA.