Ali Larijani, Iran’s new parliamentary speaker, on Wednesday warned Europe that imposing tighter sanctions immediately after offering incentives could merely provoke Tehran and instead urged world powers to send more positive signals.

Mr Larijani, a rival of Mahmoud Ahmadi-Nejad, the hardline president, expressed his frustration with the European Union’s decision this week to impose sanctions on Bank Melli, Iran’s largest bank, while speaking in parliament.