Araqchi met his counterparts from Europe on Friday to discuss the future of the Joint Comprehensive Plan of Action (JCPOA) after President Donald Trump's dramatic announcement to leave it.
"We are yet to decide whether we will stay in the JCPOA or leave it and this depends on how the other members can compensate one member's exit," the Fars news agency quoted Araqchi as saying.
"The Europeans must specifically tell us how they can guarantee Iran's interests in the deal in the absence of the US and its re-imposition of sanctions," he added.
Since Trump's May 8 decision to quit the JCPOA, other signatories of the deal -- the UK, France, China, Russia and Germany-- have had a tough task on their hands to preserve it.
Araqchi said, "The US is no longer viewed by us and other signatories as a member of the JCPOA and we will see in our Joint Commission meetings how the JCPOA can survive without America."
He said Iran and the Europeans had already discussed the sanctions and their effects on different sectors, including energy, automotive industry, transportation, aviation, banking and insurance.
Another Iranian official said Iran expects European powers to give it a package of economic measures by the end of the month to compensate Washington's withdrawal.
"We expect the package to be given to us by the end of May," he said, adding, "I'm sorry to say that we haven't seen the Plan B yet. The Plan B has just started to be figured out."
The official said the deal has been put "in intensive care" by Washington's dramatic withdrawal. "We have now a deal which is in the intensive care unit, it's dying."
While Russia and China have expressed unshakable support for the deal, the other three European governments have been torn between pleasing the US as a key ally and protecting their own interests in the profitable Iranian markets.
Trump has said he would reinstate all nuclear-related sanctions that were lifted under the deal, vowing to punish companies and countries that violate those and the harsher bans that will follow them shortly.
Iran says it will hold to its end of the deal for now but has doubts whether the Europeans can provide the solid guarantees that it has requested to salvage it.
"I am personally maybe not optimistic but... I am trying my best to come to a conclusion," the Iranian official said.