Men who have sex with trafficked prostitutes should be charged with rape, ministers believe - a move that could see thousands prosecuted.

Home Office minister Tony McNulty told The Observer: 'Whenever a man knowingly has sex with a woman against her will, that is rape,' he said. 'For example, if a trafficked woman told a man who had paid to have sex with her that she was engaged in prostitution under duress, then he could not reasonably believe that she was freely consenting. To go ahead regardless would be rape.'