The world’s big powers on Friday gave Iran a new deadline of late November to rein back its nuclear programme or face heightened sanctions, but also asked Javier Solana, the European Union’s foreign policy chief, to work on reaching a deal with Tehran.

In a tacit acknowledgment that opposition from Russia and China made speedy passage of a new United Nations sanctions resolution impossible, Condoleezza Rice, US secretary of state, agreed with her counterparts among the permanent members of the UN Security Council, Germany and Mr Solana to complete work on a new package of sanctions but to delay putting it to a vote until late November.