A retired businessman extradited to the US on charges of selling weapons parts to Iran is to change his plea to guilty after reaching a deal with prosecutors.

Christopher Tappin, 65, had always denied trying to sell batteries for surface-to-air missiles, claiming he was the victim of an FBI sting.

The BBC's Alastair Leithead said Mr Tappin would enter a guilty plea when he appears in court next week.

Mr Tappin, from London, was due to go on trial in Texas on 5 November.