Economic sanctions first imposed between 2006 and 2010 are now expected to take effect again on September 28, unless a last-minute agreement is reached with Iran.
Germany, France and the United Kingdom - known collectively as the E3 states - triggered the so-called "snapback" sanctions mechanism in late August, accusing Iran of serious breaches of the landmark 2015 nuclear accord.
They cite, among other violations, uranium enrichment far beyond levels needed for civilian purposes.
As expected, the draft resolution put forth by South Korea to keep sanctions relief in place failed to win the required nine votes in the 15-member council.
Russia and China were among the countries backing keeping sanctions relief.
Iran strongly condemned the latest UN resolution.
"Iran reserves the right to respond appropriately to this action," the Iranian state news agency IRNA quoted the foreign ministry as saying.
The Iranian UN mission also accused the United States and the E3 of taking the path of escalation instead of reason and thus being responsible for the consequences.
The three European states still have until the end of next week to negotiate concessions with Iran that could prevent the sanctions from taking effect.
However, diplomats currently consider such an outcome unlikely.
French ambassador to the UN Jérôme Bonnafont said that the three European countries were continuing to seek a solution with Iran but that they had not as yet had a "satisfactory answer" to their demands.
The UK meanwhile rejected Russia's claim that the Europeans did not have the right to reinstitute the sanctions.
In the run-up to the vote, Iran presented a new proposal.
Foreign Minister Abbas Araghchi wrote on X late on Thursday that he had submitted a "reasonable and actionable plan" to the three European countries the previous day, which is intended "to avert an unnecessary and avoidable crisis in the coming days".
Araghchi spoke of "a creative, fair, and balanced proposal which addresses genuine concerns and is mutually beneficial," without providing any details about its content.
Speaking in Geneva, Iran's Deputy Foreign Minister Saeed Khatibzadeh threatened that his country would play "strategic cards" if UN sanctions were reinstated.
While Khatibzadeh did not commit to any specific plans at the press conference, he made it clear that Iran considers withdrawal from the Nuclear Non-Proliferation Treaty (NPT) to be one of its options.
The treaty prohibits non-nuclear countries from acquiring nuclear weapons and obliges nuclear powers to disarm.
Khatibzadeh accused the E3 of fuelling tensions in the Middle East with the snapback mechanism.
"What Europeans are doing is politically biased and motivated, legally unlawful, internationally illegitimate and strategically very wrong," he said.
The 2015 Iran nuclear deal was seen at the time as a diplomatic milestone and an important instrument for restraining Iran from building a nuclear weapon.
During his first term as US president, Donald Trump withdrew the United States from the deal in 2018, with Iran responding by breaching the agreement's provisions, on enrichment in particular.
Observers believe Iran could retaliate by restricting the work of the International Atomic Energy Agency (IAEA), withdrawing from the NPT or even announcing that it will go ahead with building a nuclear weapon.
Before the June war with Israel and the US bombing of its facilities, the IAEA reported that Iran had more than 400kg of uranium enriched to 60 per cent, far beyond civilian needs and little short of the 90 per cent required for a nuclear weapon.
with AP
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