Tony Hayward, BP’s new chief executive, has prepared staff for a far-reaching shake-up of the oil company as he delivered a blunt warning that third-quarter revenues would be “dreadful”.

Mr Hayward told a staff meeting in Houston he would be announcing a streamlining of the company’s organisation next month, the Financial Times has learnt. He said that BP’s financial performance was at its lowest since the crisis of 1992-93.