BAE Systems paid more than £100m a year to Saudi Arabia’s former ambassador to Washington over more than a decade in connection with Britain’s biggest ever defence contract, according to British media reports on Thursday night.

The reports, from the BBC Panorama programme and the Guardian website, say that the sums were paid to Prince Bandar bin Sultan. Prince Bandar, who is now a national security adviser to King Abdullah of Saudi Arabia, is the son of the Saudi defence minister, Prince Sultan.