Hundreds and thousands of people marched in London on Saturday to demand another Brexit vote.
Popular Voting activists claimed that 500,000 people marched in the capital, with the mayor of London, Sadiq Khan, insisting that there would be nothing "more democratic" than having another referendum.
He said: "I can not think of anything more democratic, nothing more British, than to trust the judgment of the British.
"What we are saying is not that there should never be a calendar or the best of three, or the best of five, but what we are saying is that some of the promises made two years ago clearly have not materialized."
"No one was talking about a bad deal with the Brexit, nobody was talking about any deal at all.
"In these circumstances, for the first time, the British public should have an opinion if they accept the outcome of the negotiations, with the option of remaining in the EU."
He also told Sky News: "Jeremy Corbyn and the Labor Party are pretty clear, all options should remain on the table.
"The problem with our Prime Minister is that he can not get his cabinet to agree on a position, let alone his party or parliament.
"In those circumstances, we should take this out of the hands of the politicians in Westminster and return it to the British public.
"As I said, the important thing is to realize that nobody spoke two years ago about a bad deal with Brexit, nobody talked about any agreement." Nobody said that we would not have access to the single market, we would be outside the customs union.
"Nobody talked about harming the NHS, nobody talked about taking risks with our children and the future of our grandchildren.
"In those circumstances, I think the most democratic thing is to trust the British public to say whether they accept the agreement that the government has made or the option to remain in the EU."
The march took place in Park Lane around noon and ended in the Parliament Square with speeches by prominent leaders of the Popular Voting campaign.
A statement on the Voto del Pueblo website says: "Whether you voted with permission or remain, no one voted to make this country worse, harm jobs, damage the NHS, affect the future of millions of young people or make this country more divided. .
"The clearer the form of the final agreement with Brexit, the clearer it will be that it will not do anything to improve social justice, reduce inequality, increase our standard of living or create a better future for future generations."
Conservative parliamentary pro-Brexit mocked the march, saying it was simply another attempt to reject the democratic decision made in 2016.
The Prime Minister has already ruled out another vote to leave the European Union.
Speaking at the Conservative Party conference earlier this month, the Prime Minister attacked "prominent people" who want to stop Brexit.
Ms. May said: "There are a lot of prominent people in British politics, in parliament and outside it, who want to stop Brexit, their last plan is to call a second referendum, they call it" popular vote ", but we had a popular vote and the people decided to leave. "
Brexit Secretary of the Labor Party, Sir Keir Starmer, said the party would prefer a general election instead of a second referendum, but warned about all options. stay "At the table" in the event that Ms. May's agreement is rejected in the House of Commons.