TEHRAN – On Wednesday, Iran started to inject uranium gas into centrifuges at the Fordow nuclear facility under the supervision of inspectors from the UN nuclear watchdog.

It is the latest move by Iran to reduce its nuclear commitments in retaliation to the U.S. exit from the 2015 nuclear deal and restoration of previous sanctions and adding news ones, including a ban on Iran’s oil export.
"At the presence of inspectors from International Atomic Energy Agency, Iran started injecting (uranium) gas into centrifuges in Fordow," the Atomic Energy Organization of Iran (AEOI) said.
According to Al Jazeera, a spokesman for the IAEA said the UN nuclear watchdog’s nuclear inspectors at the site "will report back on relevant activities".
Ali Akbar Salehi, the AEOI chief, announced on Tuesday that Iran will enrich uranium to 5 percent at the Fordow facility on Wednesday.
President Hassan Rouhani declared on Tuesday that Iran starts injecting gas into centrifuges in Fordow, where 1,044 centrifuges are installed. 
Iran started to partially reduce commitments under the nuclear deal, officially known as the Joint Comprehensive Plan of Action (JCPOA), exactly year after the U.S. abandoned the deal and imposed the harshest ever sanctions on the country under the  “maximum pressure” policy. At the time Iran announced that its “strategic patience” is over.
The U.S., under the Trump administration, abandoned the deal unilaterally on May 8, 2018. 
The measure is the fourth step by Iran since it began responding to Washington's abandonment of the nuclear deal and an inaction by the remaining parties, including Europeans, to shield Iran from sanctions.
Iran took the first step to scale down nuclear commitments on May 8, 218.  The other two steps were taken two months later each. 
In the first step, Iran removed cap on its stockpile of nuclear enrichment which had been limited to 300 kilograms. In the second, Iran started enriching uranium beyond 3.67 percent. And in the third, Iran remove ban on nuclear research and development. 
Under the agreement signed between Iran, the five permanent members of the UN Security Council (the U.S., Russia, China, France, Britain) Germany and the European Union in July 2015, Tehran agreed to put limits on its nuclear work in exchange for termination of economic and financial sanctions.
Rouhani reiterated Iran’s stated position that the JCPOA can only be saved only if the remaining parties protect Iran’s from U.S. sanctions.
In his Tuesday’s declaration, Rouhani again gave the remaining sides another two months to honor their obligations otherwise his country will take the next step two months later from now.
"We can't unilaterally accept that we completely fulfill our commitments and they don't follow up on their commitments," he pointed out.
Rouhani said all the steps Iran has taken so far are reversible and Tehran will uphold all of its obligations under the deal only when the remaining signatories do the same.

PA/PA