IRISH MEP Mairead McGuinness shut down Nigel Farage's flag-waving during his final speech at the European Parliament.
The European Parliament on Wednesday gave its final approval to Britain's divorce deal from the bloc, paving the way for Brexit to take place on Friday.
Farage was greeted by cheers and the waving of union jack flags by his party's MEPs as he declared Britain was "never coming back".
But McGuinness, a member of Fine Gael and the parliament's vice president, said: "If you disobey the rules, you get cut off. Could we please remove the flags?
"Please sit down, resume your seats, put your flags away - you’re leaving - and take them with you."
In his final speech to the parliament, Mr Farage insisted there could be no turning back once Britain was out.
"This is it, the final chapter, the end of the road, a 47-year political experiment that the British frankly have never been very happy with," he said.
The Brexit Party leader said he hoped Britain's departure would start a debate across the rest of Europe about the EU's future.
"I'm hoping this begins the end of this project. It's a bad project, it isn't just undemocratic, it's anti-democratic."
Boris Johnson said the UK will make a "dignified" exit from the European Union and embark on a new chapter.
The British Prime Minister said Brexit at 11pm on Friday would be a "moment of hope" for the country.
But with the country still deeply split following the 2016 referendum, Mr Johnson said he would be celebrating in a "respectful" manner.
Answering questions on Facebook, Johnson said: "What I will be doing is, in common with everybody else, I will be making a dignified exit from the European Union.
"I will be celebrating in a way that I hope is respectful of the scale of the event, that does justice to the astonishing feat that Britain has accomplished but also is mindful of everybody's feelings about what we are doing.
"It is a great moment for our country, it is a moment of hope and opportunity but it is also, I think, a moment for us to come together in a spirit of confidence."
The prime minister will deliver an "address to the nation" an hour before the UK's departure from the bloc.
Government buildings in Whitehall will be lit up in red, white and blue to celebrate Brexit, while Parliament Square and Pall Mall will be festooned with British flags.
A light display, featuring a countdown clock, is also planned for Downing Street, while three million 50p coins will mark the occasion bearing the words "Peace, prosperity and friendship with all nations."
With additional reporting from PA