Thousands of anti-Brexit marchers have descended on Westminster to demand that Britain stays in the European Union.
Organisers estimated at least 50,000 protesters marched through central London before converging on Parliament Square on Saturday for a rally.
The People's March For Europe carries the message "unite, rethink and reject Brexit" and organisers said leaving the EU "no longer holds credibility inside Westminster, let alone on the streets of Britain".
It comes days after politicians returned to parliament following the summer recess and ahead of a critical Brexit vote.
MPs are set to vote on the repeal bill, formally known as the EU (Withdrawal) Bill, on Monday for the first time, amid concerns over the progress of Brexit negotiations.
A sea of blue and yellow Remainers amassed outside the Houses of Parliament, some draped in EU flags, while others held them aloft.
Blue wigs, berets and other headgear were in abundance, as were Exit From Brexit placards.
A few could be seen wearing blue T-shirts with the words Remoaner Till I Die.
Crowds cheered as organiser Graham Hughes opened the event, advocating for a further referendum on Britain's membership of the EU.
He was joined on stage by a man purporting to be Foreign Secretary Boris Johnson's conscience and a Theresa May puppet.
Sir Ed Davey, Liberal Democrat MP for Kingston and Surbiton, told the crowd he was "embarrassed" for Great Britain.
He said: "I've gone from anger to distress, from fury to despair. But since the Brexit negotiations begun there's a third emotion I've been feeling.
"Embarrassment. Embarrassment at our country's leaders. Embarrassment for Great Britain."
After being interrupted by boos, he said he felt embarrassed "that these shambolic people are supposed to be representing us. They can't even negotiate".
He said he wanted to personally thank Conservative and Labour Remainers who voted for him to be their MP, so he could continue to oppose Brexit.
The blue and yellow demonstrators fell silent for one minute in respect for the victims of the Grenfell Tower fire, breaking into applause as the 60 seconds ended.
A Sikh leader local to the North Kensington community, Bhupinder Singh, led them in the period of reflection.
The volunteer said: "Never have I experienced this much prejudice, racism and the difference between rich and poor.
"The Brexit vote has led to a 'them and us' society which we never had.
"The Brexit vote has led to a rich and poor. The Brexit vote has led to an increase in racism."