U.S. President Donald Trump has been a strong critic of the agreement, known as the Joint Comprehensive Plan of Action (JCPOA), under which Tehran agreed to limit its nuclear program in exchange for sanctions relief.
Iran's foreign minister said on Thursday that demands by U.S President Donald Trump to change Tehran's nuclear deal with world powers were unacceptable, as a deadline set by US for Europeans to "fix" the deal loomed.
All this comes less than two weeks before Donald Trump is due to decide whether to continue to abide by the 2015 deal by waiving United States sanctions on Iran.
Ali Akbar Velayati, senior foreign policy adviser, said on Thursday that while Iran is committed to the nuclear deal, it will withdraw if any changes are proposed or if Washington rejects.
A presentation by Israeli Prime Minister Benjamin Netanyahu on Monday about what he said was documentary evidence of Tehran's past nuclear arms program could give Trump a fresh argument to withdraw, even though United Nations inspectors say Iran has complied with the terms of the deal.
In a televised presentation at the Israeli Ministry of Defense on Monday, Israeli Prime Minister Benjamin Netanyahu claimed that Iran is running a program called Project Amad that is aimed at "developing five nuclear warheads".
UN Secretary-General Antonio Guterres has warned of "dangerous times" as US President Donald Trump considers whether to remain in or leave the global deal that seeks to rein in Iran's nuclear weapons programme.
"We should not scrap it unless we have a good alternative", he said.
"The nuclear deal is based on lies". "We face risky times".
These included what happens when the current deal expires in 2025, Iran's ballistic missile programme and its "destabilising regional activity", they said in a statement.
"I don't know what the USA president will decide on May 12", Macron said during a visit to Sydney.
Iran denies seek to build a nuclear weapon, or ever breaching the 2015 agreement.
A decision by Trump to end USA sanctions relief would all but sink the agreement and could trigger a backlash by Iran, which could resume its nuclear arms programme or "punish" U.S. allies in Syria, Iraq, Yemen and Lebanon, diplomats said.
Top aides are not seeking to talk Mr. Trump out of withdrawal because he seems intent on it, a second White House official said. Iran maintained that it had only been pursuing nuclear energy.
The three European countries that signed the agreement, Britain, France and Germany, have repeatedly tried to persuade Trump not to withdraw.
Velayati warned against any move to try to renegotiate the 2015 deal.