US presidential hopeful Herman Cain has said he is suspending his campaign for the Republican nomination. He blamed political and media pressure on his family in the wake of "false" allegations of sexual harassment and a 13-year-long extra-marital affair. "I am not going to be silenced and I'm not going away," he told supporters in his home city of Atlanta, Georgia. Next month, voters in Iowa will begin the process of choosing a Republican presidential candidate for 2012. He said the "false" allegations against him had taken a toll on his family, but, he added: "I am at peace." He said he would endorse another candidate at a later date but gave no hint of where he would direct his supporters to go. On Friday Mr Cain discussed with his wife, Gloria, whether to press on with his campaign.