Iran will begin enriching uranium at its Fordo underground facility on Wednesday, canceling another 201
President Hassan Rouhani said the move would be reversible if the world powers involved in the agreement, support their commitments.  Enriched uranium can be used for the production of reactor fuel, but also for nuclear weapons.
This is the fourth step taken by Iran since July in response to sanctions restored by the United States in refusing a deal.
The 2015 Agreement was intended to limit. Iran's nuclear ambitions in return for sanctions relief, but President Donald Trump unilaterally withdrew from it in May 2018.
Mr Trump wants to force Iran to negotiate a new agreement that puts unlimited restrictions on its nuclear program and also stop its development. of ballistic missiles. But Iran has so far refused.
Other parties to the deal – United Kingdom, France, Germany, China and Russia – tried to keep him alive. But the sanctions led to a collapse in oil exports from Iran, the value of its currency went down and sent a rise in inflation.
Iran insisted that its nuclear program was completely peaceful.
Prior to 2015, the country had two enrichment facilities – Natanz and Fordo – where uranium hexafluoride gas was fed into centrifuges to separate the farthest isotope, U-235.
The deal saw Iran agree to produce only low enriched uranium, which has a 3-4% concentration of U-235 and can be used to produce fuel for nuclear power plants. Weapon-grade uranium is enriched by 90% or more.
Iran also agreed to install no more than 5,060 of the oldest and most efficient centrifuges in Natanz by 2026 and not to enrich any Fordo by 2031. 1,044 centrifuges
In a speech broadcast by state-owned television on Tuesday, the Iranian president announced, "We will start introducing gas into Fordo tomorrow."
Mr Ruhani said the move would be under the supervision of the global nuclear watchdog, the International Atomic Energy Agency (IAEA) ).
He added that Iran was aware of the "sensitivities" of other parties to the deal on a Fordo, which was covertly built about 90 meters (300 feet) below a mountain south of Tehran to protect it from air strikes.
"But at the same time as they commit, we will end the gas again … so it is possible to reverse this step."
On Monday, the head of the Iranian Atomic Energy Organization (AEOI) said. that there are double the number of advanced centrifuges that are operated at Natanz.
Ali Akbar Salehi told reporters that he now owns 60 IR-6 centrifuges and that he can enrich uranium to 20% concentration "within four minutes" of receiving an order. Earlier, he said the AEOI would take four days to do so.
Russia stated that it was monitoring the situation in Iran "with concern" following Mr Rouhani's announcement.
"We support the continuation of this deal," a spokesman for President Dmitry Peskov told reporters in Moscow.
There is no comment from the European Union, but a spokesman for its foreign policy chief said on Monday that Member States have been "consistent in saying that our commitment to the nuclear deal depends on full compliance with Iran."