The US said on Monday that it was prepared to use “all means necessary” to prevent Iran from gaining nuclear arms, highlighting the potential threat to regional and global stability. “Iran should take actions to build international confidence and de-escalate tensions, not continue nuclear provocations that pose grave proliferation risks,” John Kelley, US political counsellor, told the UN Security Council. “The United States is fully committed to resolving the international community's concerns regarding Iran's nuclear programme through diplomacy. Unfortunately, Iran's actions suggest this goal is not its priority. “We remain postured and prepared to use all means necessary to prevent a nuclear-armed Iran.” Last month, the International Atomic Energy Agency said that Iran now has enough uranium enriched to up to 60 per cent purity for three atom bombs. The agency reported that Iran's total stockpiles of enriched uranium now stand at 22 times the JCPOA limit. Uranium enriched at 60 per cent purity is a short, technical step away from weapons-grade levels of 90 per cent. Mr Kelley accused Iran of continuing to take increasingly provocative steps to expand its nuclear activities. “Iran is not only failing to co-operate with the IAEA to resolve outstanding safeguards issues, but also wilfully hampering the agency's verification and monitoring activities,” he stressed. UN political chief Rosemary DiCarlo stressed that UN Secretary General Antonio Guterres still considers the JCPOA “the best available option to ensure that the Iranian nuclear program remains exclusively peaceful.” She urged Iran to reverse course, as did Germany, France and Britain in a joint statement. “Iran has developed and tested ballistic missiles and related technologies extensively in complete disregard for this resolution, undermining global non-proliferation principles and architecture. This requires particular scrutiny,” read the statement. To prevent Iran from developing nuclear weapons, the Joint Comprehensive Plan of Action of 2015 was struck between Tehran and world powers. In the agreement, Iran agreed to restrict its uranium enrichment to the extent needed for nuclear energy in return for the removal of economic sanctions. UN inspectors were given the task of monitoring the programme. Efforts to revive the JCPOA remain frozen following a breakdown in negotiations last year and subsequent political developments that have led to a further deterioration in relations between the parties. Both Iran’s UN Ambassador Amir Iravani blamed Washington's withdrawal from the JCPOA, Western sanctions and an “anti-Iran” stance for the current standoff. Mr Iravani said Iran is allowed to enrich uranium for peaceful purposes under the Nuclear Nonproliferation Treaty. He told the 15-member Security Council that Tehran has persistently worked towards the revival of the JCPOA agreement and engaged in substantive talks with the EU. He accused the US and Europe of a lack of sincerity and emphasised that Iran has consistently refrained from enriching uranium beyond 60 per cent. “Iran has always complied with its obligation on the safeguards agreement, and has rendered maximum co-operation to enable the IAEA to effectively implement its verification activities in Iran.”