The start of Britain's official 10-week EU Referendum campaign got well underway on Friday, with advocates from both the Leave and Remain groups battling it out to win public support.
On June 23, U.K. citizens will decide their country's future relationship with the European Union (EU), and whether they want to be part of a reformed union, or exit the bloc.
British Chancellor of the Exchequer George Osborne told CNBC on Friday the referendum is "a big democratic exercise" that helps to resolve uncertainty about the U.K.'s role in the EU. He said he hopes Britain will remain in the union and then "get to work on reforming the EU."
"We're clear — leaving would cause an economic shock and a long-term economic cost for the U.K. And that's one of the messages British voters are hearing," he said in the interview from Washington, D.C.
He noted that departure could deter investment in Britain and possibly trip up "one of the fastest growing advanced economies in the world."