BRUSSELS

EU Commission President Jean-Claude Juncker on Thursday claimed U.K. Prime Minister Boris Johnson told "lies" during the Brexit referendum campaign.

So many "lies" were told about Europe's reality during the referendum campaign, Juncker said at a forum in Brussels.

He said then-Prime Minister David Cameron asked him not to intervene in the referendum campaign, adding that this had been a "major mistake". "I should have intervened because nobody was denying, contesting the lies Boris Johnson and others were spreading around," said Juncker.

U.K. voters decided to leave the EU in a 2016 referendum with a small margin.