A petition demanding a final say on the terms the UK leaves the EU has been delivered to UK parliament.
More than one million people have signed the campaign, which was launched by the editor of The Independent.
The petition is calling for the public to be given a vote on the final Brexit divorce bill when it leaves the bloc at the end of March.
Politicians Chuka Umunna, Justine Greening, and Caroline Lucas handed the campaign to British Prime Minister Theresa May at 10 Downing Street.
Politicians will vote on Theresa May's Brexit deal agreed with the EU on December 11.
However, it is believed she will not get enough support from the House of Commons, which could see the UK leave the EU without a deal.
May is under pressure over the legal advice the government received on Brexit.
Attorney General Geoffry Cox is due to release a document regarding this on Monday.
The opposition Labour party said the UK would face a "constitutional crisis" if May does not make the advice fully public.
Speaking to the UK news channel ITV, May called on MPs to support her deal and said: This is not any old vote, this is delivering on what people voted for in the referendum and it is important for us as politicians to remember that."