The UN arms ban is set to expire in October as per UNSC Resolution 2231 that endorsed Iran’s 2015 nuclear deal with world powers, formally called the Joint Comprehensive Plan of Action.
The US has already exited the deal unilaterally and restored tough sanctions on Tehran for two years. It is now pushing for an indefinite extension of the arms embargo.
It has prepared a draft UN resolution to be put up for a vote at the security council.
US Secretary of State Mike Pompeo announced on Wednesday that Washington would put forward the resolution despite ardent opposition from Russia and China.
UN diplomats say opposition to the resolution's current form is so widespread that Washington is unlikely to secure the nine votes required to force Moscow and Beijing to exercise their vetoes.
The US text, seen by AFP, effectively calls for an indefinite extension of the embargo on Iran and uses hawkish rhetoric.
"The resolution takes a maximalist position on Iran," one diplomat told AFP.
Another diplomat said the draft "goes beyond the current provisions" of the ban on conventional weapons sales to Iran that ends on Oct. 18.
"This is a car crash that everyone knows is going to happen," New York-based UN expert Richard Gowan told AFP, describing the US draft as a "poison pill of a text".
Alternative Resolutions
European allies of the US who signed the deal with Iran, along with their Russian and Chinese counterparts, have voiced support for extending the conventional arms embargo but their priority is to preserve JCPOA.
UN-watchers suggest that EU countries in the council could be brought on board by a short-term extension of the embargo if it helps preserve the nuclear deal.
France, Germany and Britain hope to draft a resolution that satisfies China, Russia and the US, while preventing them from vetoing it.
It reportedly involves limiting the potential volume of arms deals with Iran and extending the ban in a limited timeframe.
They may possibly propose their own draft resolution, according to UN diplomats, but finding consensus is likely to be difficult with China and Russia intending to veto.
“China firmly upholds the authority of the Security Council resolution and the efficacy of the JCPOA. We don't agree with the US in pushing for the extension of the arms embargo against Iran in the Security Council,” Chinese Foreign Ministry Spokesperson Wang Wenbin said at a press briefing on Thursday.
He stressed once again that all the provisions of Resolution 2231, including the relevant arrangements with regard to arms embargo, should be implemented in earnest.
JCPOA at Risk
Iran has informed UNSC members that the extension of arms embargo against the country is not acceptable to the Islamic Republic and would receive its firm response.
Ali Shamkhani, secretary of Iran’s Supreme National Security Council, has even warned that JCPOA would "die forever" should the arms restrictions remain in place.
The US has threatened to trigger the return of all UN sanctions on Iran through the so-called snapback mechanism envisioned in the JCPOA, if the arms ban on Iran is not extended.
The move is based on the argument that Washington remains a "participant" in the nuclear accord, as it was listed in Resolution 2231.
Kelly Craft, the US ambassador to the UN, told journalists on Thursday that Washington's first objective was an extension but it is prepared to use "all tools available".
European allies have been skeptical on whether Washington can force sanctions and warn that the attempt may delegitimize the UN Security Council.
A push for snapback "seems very likely", according to Gowan of the International Crisis Group think-tank.
"At worst, that could torpedo the nuclear deal once and for all, which may be what Pompeo wants.”