By Paul Carsten BEIJING (Reuters) – China will force real-name registrations on users of instant messaging tools and require public accounts wishing to publish or reprint political news to seek prior approval, state media said on Thursday. Last year, China launched a campaign to clamp down on online rumour mongering and clean up the internet. The crackdown has led to an exodus of users from Twitter-like microblog platforms such as Weibo Corps Weibo after authorities detained hundreds of outspoken users. The latest restrictions will likely affect hugely popular mobile messaging apps like Tencent Holdings Ltds WeChat, which has almost 400 million users.