The UN nuclear agency’s confirmation that Iran has expanded its uranium enrichment programme sets the stage for difficult negotiations on new UN sanctions, with the US, Britain and France again likely to seek tougher measures than Russia and China will accept.

The US accused Iran of “cynically” pursuing nuclear weapons today, saying Tehran’s claims that its aims were peaceful constituted wilful deceit of the world.

IRAN escaped UN censure over its nuclear programme yesterday but Washington, which accuses it of seeking an atomic bomb, said it reserved the right to take the case to the Security Council.