"We stand ready to put in action President Hassan Rouhani's latest position that if Tehran were not able to export its crude oil through the Strait of Hormuz, no other country would be able to do so", Jafari was quoted as saying in Iran's state-controlled press.
"The concerns, which we had last night and which were also expressed by President Rouhani, were addressed in the meeting and more details were disclosed, and they make us more optimistic than we were yesterday", he said.
Zarif pointed to his "very serious and constructive" talks with the remaining parties of the nuclear deal and said, "I believe that there is political will to continue work and save this agreement but we must see what will happen to this issue in practice."
A senior US military leader said in 2012 the Guards have the ability to block the Strait of Hormuz "for a period of time" but the United States would take action to reopen it in such an event.
European Union foreign policy chief Federica Mogherini says world powers and Iran have agreed to continue talking, including on economic measures, over how to save the 2015 nuclear deal.
It must activate a "blocking statute" - legislation banning EU companies from complying with United States sanctions on Iran - and allow the European Investment Bank (EIB) to do business in Iran, he said.
As an original signatory to the deal, the United States - under then-President Barack Obama - also pledged to waive secondary American sanctions as long as Iran continues to abide by the agreement. Washington has since told countries they must stop buying Iranian oil from November 4 or face financial measures.
"All the commitments made today, should be implemented before the August deadline.it is up to the leadership in Tehran to decide whether Iran should remain in the deal. the proposal was not precise and a complete one", Mohammed Javad Zarif told reporters.
"We are meeting here today to make sure the nuclear agreement with Iran has a future", German Foreign Minister Heiko Maas said as he arrived for talks with counterparts from Iran and the other signatories Britain, China, France and Russian Federation.
US President Donald Trump signs a document reinstating sanctions against Iran after announcing the US withdrawal from the Iran nuclear deal, in the Diplomatic Reception Room at the White House in Washington, DC, on May 8, 2018.
"We must put in place measures that allow Iran to trade as long as it meets its commitments", he told RTL radio in France, cautioning that the new steps may take until November when numerous sanctions take effect.
It is unsurprising that the U.S. is using this as an excuse to issue a bunch of new statements about their military commitment, and is liable to be an excuse for more USA naval operations along the Iranian coast.
Since Trump's announcement, Iran's rial currency has fallen, prices have risen and the country has been hit by street protests and strikes.
On Jun 30 authorities say they have foiled an alleged plot to bomb a rally by an exiled Iranian opposition group based in France also attended by leading USA figures including former NY mayor Rudy Giuliani, Trump's personal lawyer.