The Duke of Cambridge has met mental health campaigners at 'Campaign Against Living Miserably' (CALM), a charity dedicated to preventing male suicide, to lend his support to their 'Best Man Project'. During a panel discussion, the Duke joked that Prince Harry has not yet asked him to the best man at his upcoming wedding to Meghan Markle, and added that he is "still working" on the diary clash that sees the Royal nuptials on the same day as the FA Cup final. Report by Chulanin. Like us on Facebook at http://www.facebook.com/itn and follow us on Twitter at http://twitter.com/itn