Iran said Sunday its arch-foe the United States is facing "maximum isolation" after major powers dismissed a unilateral US declaration that UN sanctions on Tehran were back in force.
Washington said the sanctions had been re-activated under the "snapback" mechanism in a landmark 2015 nuclear treaty -- despite Washington having withdrawn from the deal.
As other signatories cast doubt on the move having any legal effect, Washington threatened to "impose consequences" on states failing to comply.
But Iran's President Hassan Rouhani said a concerted campaign by Washington to pressure Tehran had backfired.
"We can say that America's 'maximum pressure' against Iran, in its political and legal aspect, has turned into America's maximum isolation," he said in a televised cabinet meeting.
The sanctions in question had been lifted when Iran, the UN Security Council's five permanent members (Britain, China, France, Russia and the US) and Germany signed the 2015 treaty on Iran's nuclear programme, known as the Joint Comprehensive Plan of Action.
But President Donald Trump withdrew the US from the JCPOA in 2018, saying the deal -- negotiated by his predecessor Barack Obama -- was insufficient.
He also stepped up Washington's own sanctions as part of a "maximum pressure" campaign against the Islamic republic.
The US insists it is still a participant in the agreement -- but only so it can activate the snapback option, which it announced on August 20.
Virtually every other UNSC member disputes Washington's ability to execute this legal pirouette, and the UN body has not taken the measure any further.
- 'No legal effect' -
On Sunday, France, Germany and Britain issued a joint statement saying Washington's "purported notification" was "incapable of having any legal effect".
Russia also said Washington's "illegitimate initiative and actions" could not have "international legal consequences" for others.
China's mission to the UN tweeted that the US move was "devoid of any legal, political or practical effect", adding that it was "time to end the political drama by the US".
Rouhani thanked UNSC members who had "stood against America's illegal request" and said if remaining signatories let Iran access the deal's economic benefits, Iran would reinstate nuclear commitments it had dropped in response to the US withdrawal.
Secretary of State Mike Pompeo, announcing the move, said Saturday that the US "welcomes the return of virtually all previously terminated UN sanctions on the Islamic Republic of Iran".
He said US authorities were prepared to impose "consequences" against states who "fail to fulfil their obligations to implement these sanctions", with measures to be announced in the coming days.
With around six weeks to go until the US presidential election, Trump could unveil those measures in a speech at the UN General Assembly on Tuesday.
Iran's foreign minister accused Pompeo of "threaten(ing) to punish a world that refuses to live in his parallel universe".
"The world says NO Security Council sanctions were restored," Mohammad Javad Zarif tweeted.
Iran's foreign ministry said in a statement that Washington, by leaving the nuclear deal, had "explicitly denied itself any right" to use the "snapback" mechanism.
It also warned that if the US "acts on these threats, directly, or with the cooperation of a handful of its puppets, it will face a serious response and be responsible for all the dangerous consequences".
- 'Nothing worse' -
The US had already suffered a resounding defeat at the Security Council in mid-August, when it tried to extend an embargo on conventional weapons deliveries to Tehran, which was due to expire in October.
Pompeo responded with an unusually vehement attack on Britain, France and Germany, accusing them of "siding with Iran's ayatollahs", before announcing the snapback.
In Washington's eyes, its move has now extended the embargo "indefinitely" and reactivated international sanctions on many activities related to Tehran's nuclear and ballistic missile programmes.
Zarif accused Pompeo of not having read UN resolutions or the nuclear deal.
"He's now probably waiting for the movie to come out so he can begin to understand it," he told state television.
On the streets of Tehran, Iranians complained of harsh economic conditions they blamed on US sanctions.
"It's really difficult for the people right now. Whether sanctions are reimposed or not, we are living with utmost difficulty," said Leila Zanganeh, a martial arts instructor.
But Danial Namei, an architect, seemed to care little for returning UN sanctions and doubted things could get worse.
"We've been through difficult things and it is still ongoing. There's nothing worse than the worst, after all," he said.