Iran has indicated it will respond on Thursday to a crucial international offer regarding its nuclear programme, amid hopes among world powers that it will accept a deal to transfer about two-thirds of its current stock of low-enriched uranium to France and Russia.

However, Iranian media once again signalled on Wednesday that Tehran would be seeking changes to a draft plan drawn up by the International Atomic Energy Agency, a move that could force the deal to unravel if Tehran’s demands were seen as excessive by world ­powers.