Rupert Murdoch brokered a “tentative truce” between his Fox News network and Barack Obama at a secret meeting with the Democratic presidential nominee, accor­ding to the author of a book on the News Corp chairman.

Fox News is seen by the Obama campaign as among its most hostile critics. Mr Obama initially rebuffed efforts by the Kennedy family to secure a meeting with News Corp executives, Michael Wolff writes in the current issue of Vanity Fair.