Hundreds of thousands of people took to the streets in London city on Saturday to demand second Brexit vote.

Iran PressEurope: Hundreds of thousands of supporters of the European Union marched through London in the biggest demonstration so far to demand that the British government holds a public vote on the terms of Brexit, Reuters reported.

The protesters waved the blue and gold flag of the EU and held up “Bollocks to Brexit” banners under sunny skies to call for another referendum on the eventual deal on how Britain will leave the world’s biggest trading bloc.

Organisers said about 700,000 people took part in the march, which would make it the largest in Britain since a demonstration against the Iraq war in 2003.

The “People’s Vote” campaign, which includes several pro-EU groups, said they had stewards stationed at regular intervals to estimate the size of the crowd. The police did not provide an independent estimate of numbers participating.

Protesters originally gathered near Hyde Park and then walked past Downing Street and finished outside parliament where they listened to politicians from all main political parties.

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The march comes after another tumultuous week for Britain's Prime Minister Theresa May in which she failed to agree a divorce deal with EU leaders in Brussels and infuriated members of her own party by making further concessions in the talks.

With just over five months until Britain is due to leave there is no clarity about what a future trade deal with the EU will look like and some rebels in May’s Conservative Party have threatened to vote down a deal if she clinches one.

James McGrory, one of the organisers of the march, said voters should have the chance to change their minds because the decision will impact their lives for generations.

“People think the Brexit negotiations are a total mess, they have no faith in the government to deliver the promises that were made, partly because they cannot be delivered,” he said.

At the march, demonstrators carried placards saying “Brexit is pants”, “Time for an EU turn” and “European and proud.”

Britain's Prime Minister Theresa May recently published white paper calls explicitly for the U.K. to leave the EU’s customs union and single market, while demanding a new “facilitated customs arrangement” under which, “as if in a combined customs territory with the EU, the U.K. would apply the EU’s tariffs and trade policy for goods intended for the EU. The U.K. would also apply its own tariffs and trade policy for goods intended for consumption in the U.K.”

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