LIVE: Cops watch on as protesters gather outside debate between Trump and Harris in Philadelphia

DONALD Trump and Kamala Harris’ first-ever presidential debate is underway. Trump and Harris shook each other’s hands before the debate started and the former president told her to have fun. The clash is taking place at the National Constitution Center in Philadelphia. The two nominees are going head-to-head in a 90-minute event moderated by ABC’s David Muir and Linsey Davis. Harris and Trump did not make opening statements and their microphones are muted while the other is talking. The candidates have two minutes to answer a question and have a two-minute window to debate. Read more: The Sun delivers breaking news, latest gossip and incredible exclusives around the world with hubs in London, New York, Scotland and Ireland. Covering topics from news, money and sport along with our famous Fabulous Magazine, The Sun is the biggest news brand i