TEHRAN (Reuters) - France’s foreign minister visited Iran on Monday on a delicate mission to reaffirm Europe’s support for a nuclear deal that opened Iran’s economy, while echoing U.S. concern about Tehran’s missile program and role in regional conflicts.

Iranian President Hassan Rouhani shakes hands with French Foreign Affairs Minister Jean-Yves Le Drian, in Tehran, Iran, March 5, 2018. President.ir/Handout via REUTERS

Jean-Yves Le Drian’s visit reflected French efforts to safeguard Iran’s 2015 accord with major powers. U.S. President Donald Trump has threatened to pull out unless three European signatories help “fix” the deal by forcing Iran to limit its sway in the Middle East and rein in its missile program.

Iran’s clerical rulers believe that even if it were to do so, as called for by Western leaders, the United States is bent on “regime change” in the Islamic Republic and therefore any concessions would be futile.

After a day of tough talks with senior Iranian officials, who all repeated that Tehran would not bow to Western pressure to scrap its ballistic missile tests, Le Drian said there remained “much work to do” with Iran.

“We’re not going to be Donald Trump’s envoys or Iran’s defense lawyers,” said a French diplomatic source. “We have our own concerns and will talk to the different sensibilities of the Iranian system to get our point across.”

Iran’s elite Revolutionary Guard Corps, which answers only to its ultimate political authority, Supreme Leader Ayatollah Ali Khamenei, runs the missile program.

“Our missile work is... in line with our defensive policy, which poses no threat to any country,” the secretary of Iran’s Supreme National Security Council, Ali Shamkhani, told Le Drian, according to state TV.

To send a message to France, Iranian media said, Shamkhani appeared in military uniform in his meeting with Le Drian.

Earlier, the semi-official Tasnim news agency quoted an Iranian armed forces spokesman as saying Iran’s missile development would “continue non-stop and foreign powers have no right to intervene on this issue”.

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Hardline Iranian media reacted angrily to Le Drian’s visit with headlines like “The Rude Guest” and “Weapons of mass seduction”. Fars news agency said a group of hardliners gathered at Tehran’s International Mehrabad Airport and in front of Iran’s Foreign Ministry to protest at Le Drian’s visit.

The deal with France, Britain, Germany, Russia, China and the United States gave Iran relief from economic sanctions in return for curbs on its disputed nuclear activity, allowing Tehran to talk trade with Europe for the first time in years.

ECONOMIC BENEFITS SLOW TO ARRIVE

But so far the deal, pragmatist President Hassan Rouhani’s headline achievement, has yet to deliver the economic benefits many Iranians yearn for. That has impeded efforts by Rouhani efforts to engage with the West, an approach opposed by hardline allies of Khamenei in the clerical and security establishment.

France has been quick to restore trade ties. Planemaker Airbus, oil major Total and automobile manufacturers Peugeot and Renault have signed deals, all at risk if Trump walks out of the accord.

In an effort to keep him on board, French President Emmanuel Macron has criticized Iran’s missile program and raised the possibility of new sanctions. On the eve of Le Drian’s visit, Macron told Rouhani by phone that France expects Iran to make a “constructive contribution” to solving crises in the region.

Tehran supports Syrian President Bashar al-Assad against rebels, including groups backed by the West, and also backs Israel’s enemy Hezbollah in Lebanon.

“France will continue discussions with Iran...but must find a way to restore stability in the region,” Le Drian told reporters, adding that Iranian leaders voiced extreme concern over Syria’s humanitarian disaster after seven years of war.

Iranian Foreign Minister Mohammad Javad Zarif told Le Drian that the European signatories of the nuclear deal “should play a more active role to keep the accord alive.

“Supporting the accord verbally is not enough ... If the EU is trying to salvage the accord..., they should try to keep Iran, not the U.S., in the accord,” he said, state TV reported.

Le Drian also met with Rouhani, who told the French minister that Tehran would not be the first to violate the nuclear accord, according to state television. U.N. nuclear inspectors have repeatedly verified Iranian compliance with the agreement.

France says Iran has been committed to the terms of the deal, but argues that Tehran may be violating part of the U.N. resolution enshrining the accord. The resolution calls on Tehran to refrain from work on missiles designed to carry nuclear warheads, although this is not in the accord itself.

“On the ballistics, the Iranian program is not compatible with (the resolution) and we have a particular concern on the transfer of know-how of ballistic capacity to regional actors, and by that we mean Hezbollah,” the diplomatic source said.

In a warning to Trump, the head of the U.N. nuclear watchdog agency in Vienna on Monday that a collapse of the nuclear deal would be a “great loss for nuclear verification and for multilateralism”.