Nigel Farage told fellow MEPs "you're not laughing now" as he was barracked and booed at an emergency meeting of the European Parliament to discuss Brexit.
At a highly charged session in the Brussels chamber, EU Commission president Jean-Claude Juncker also questioned why the Ukip leader had attended the session following the Brexit vote.
Jean-Claude Juncker has said the European Parliament "must respect British democracy" following last week's EU referendum.
Speaking at an emergency session to discuss the Brexit vote, the European Commission President's comment was met with applause by the parliament - and a slow clap by Nigel Farage.
Juncker turned to the UKIP MEP and responded in an amused tone: "That's the last time you are applauding here."
"And to some extent I am surprised you are here," he added. "You were fighting for the exit. The British people voted in favour of the exit, why are you here?"
The Democratic presidential candidate may also have shown his cards on his choice of running mate.
The US president also shared a post on Twitter accusing Dr Anthony Fauci of misleading the public over hydroxychloroquine.
Fears over an impending second wave of coronavirus dominates Wednesday’s front pages.