Seven Iranians were killed in strike on Syrian air base: Tasnim

These comments are supposed to "warn" the U.S. and the other signatories to the nuclear deal against making changes to the deal, which at present largely benefit Iran and no other country.

Some foreign-exchange traders attributed the slide to "opportunistic speculation" among dealers who sought to exploit existing worries about Iran's broader economic health, its continued inability to access overseas financing and the fragility of the nuclear deal.

"We will not be the first to violate the accord but they should definitely know that they will regret it if they violate it", Mr Rouhani told a conference to mark National Nuclear Technology Day in Tehran.

On Monday, Iran unveiled "84 achievements" in the field of nuclear technology including "a nuclear battery and centrifuges for the oil industry, nuclear fission, nuclear medicine and power plants".

Iran's Fars news agency said "four Iranian military advisers" were killed in Monday's attack on the military airport.

US President Donald Trump and French counterpart Emmanuel Macron have vowed a strong response to the suspected poison gas attack, which left dozens dead, and the UN Security Council was expected to discuss the crisis later today.

"We do not officially recognize any other rate than this one", he said. "They will witness the fallout in less than a week", Rouhani said during the ceremony, according to Iran's state-run Press TV.

In 2017, Iranian atomic official Behrouz Kamalvandi said that Iran's nuclear programme could "soar" if they wanted it to, which would probably invite the revamp of the Arak heavy water facility.

Enriching uranium to 20 percent is considered above the requirement for nuclear energy production, but still well below the 80 to 90 percent enrichment required for a nuclear weapon. "We are hoping that there will be no need for that, but if there is, it will be a scientific challenge".

The Iranian President made the remarks on Monday while receiving the Chairman of the State Duma of the Federal Assembly of the Russian Federation, Vyacheslav Volodin, in Tehran. United States sanctions will resume unless Trump issues new "waivers" to suspend them on May 12.

The deadline is on May 12, although he hinted that the United States could cut loose before that date if he sees no progress in negotiations.