- Organizers estimate 50,000 people are attending the rally
- Voters say they feel cheated by a campaign of lies
London (CNN)They simply won't take "Brexit" for an answer.
Tens of thousands of protesters angered by Britain's historic vote last week to leave the European Union marched down London's up-market Park Lane Saturday, many of them hoping that divorce from the bloc will never actually happen.
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They say they've been cheated by a campaign deceit and false promises, chanting "We are the 48%, no more lies, no more hate." The Leave vote won 52% of the vote, with the remain side at 48%.
Organizers said around 50,000 people had joined the march by midday, and while the protest attracted all walks of life, millennials appeared to make up the bulk of the crowd.
'We want action'
"The votes were called but people were told lies," said 29-year-old Loveday Newman, wearing a T-shirt bearing a big red heart with "Europe" scrawled on it.
"I understand it's the outcome of a democratic vote but it's still a democracy, and being part of that I hope we can contest the outcome. I hope we remain. I am European. Britain is just stronger in," she said.
Tom Walsh, a 31-year-old factory worker, said he felt the "wrong thing has happened."
"Both sides have lied. We've been part of Europe for so long -- you can't change anything being alone. And to the EU, we're not racist idiots. They represent a small number of people here. You're always welcome," he said.
Britain has seen a rise in racial hate crimes following the vote.
Organizers of the March for Europe protest said they were demanding decisive political action as the country plunged into political chaos and uncertainty following the vote.
"We're all here today under one message -- we believe in the EU and we want our voices heard. We want action taken by the government," March for Europe spokeswoman Helen Parker told CNN.
"There is a complete lack of leadership and it's just chaos in government. There's no plan for this country and everybody's worried about the future," she said.
Protesters' signs referred to concerns about the economy, democracy and security, and complained of muddied information by campaigners and the media.
One protester held a sign reading "Divided Europe is a dangerous place," while another read "Media & MPs: Shame on You."
"Brexit = Business Exit," another read, as concerns grow of mass job losses if a withdrawal from the 28-country bloc prompts businesses to set up headquarters and factories elsewhere.
Some of those joining the march were people who did vote to leave but then changed their minds in the aftermath, when the pound plunged and global markets took a nosedive. Others stood by their leave votes, but called for better leadership and a good relationship with the EU as Britain exits.
British Prime Minister David Cameron, who campaigned to keep Britain in the union, announced his resignation the day after the vote, saying he would step down in October.
That has left the country without a clue as to who will usher them into a new and uncertain political phase, and Cameron has said the separation process will not officially start until the new prime minister is appointed.
The British public has no more certainty of the opposition Labour Party, also torn apart by leadership tussles following the referendum.
Many are interested in what kind of trade deal Britain will strike with the EU, as it could have significant consequences for the country's economy.
The majority of London voters supported remaining in the union, and Mayor Sadiq Khan has reiterated that the city is an outward looking one that is open to Europeans.