Labour has hailed its one-day festival of music and political debate as a success, despite criticism and ridicule from the opposite side of the political divide.

The party said 13,000 people bought advance tickets for the event and “many more” turned up on the day, while MPs and supporters tweeted photographs showing crowds of people listening to a speech from the leader, Jeremy Corbyn.

The event had been written off as a vanity project in the days beforehand as prices were cut owing to poor ticket sales.



But on the day Corbyn, echoing his appearance at Glastonbury last year, was welcomed on to the stage to chants of “Oh, Jeremy Corbyn” and cheered throughout a 25-minute speech.

“The legacy of the next Labour government will be a national and education service that takes the commodity out of education,” he said. “Under Labour, mail, rail and water will come back where they belong, into public ownership,” he said. “It will be democratic and it will be well run.”

But he also faced criticism from some in the crowd. During his speech, pro-EU campaigners unfurled a banner calling on Corbyn to “stop backing Brexit”, while others wore stickers with the slogan “Bollocks to Brexit”.

Mark Wallace, the editor of ConservativeHome, joked that the event had run out of Trade Union beer, tweeting: “Even I expected it to take longer than five and a half hours for Corbynism to produce shortages.”

Composite image showing the variety of T-shirts supporting Jeremy Corbyn at the Labour Live event. Photograph: Rick Findler/PA

But the Labour supporter Owen Jones, who was part of the line-up in the Solidarity tent, insisted the event had been a huge success. He tweeted a picture showing thousands of people and wrote: “They said Labour Live wouldn’t work. They sneered at it. They mocked it. Thousands came, listened to music, heard speeches, discussed politics and will leave inspired. Share this photo everywhere to show the naysayers were wrong.”

Ticket sales had been poor in the lead-up to the event, according to insiders. At the end of May, Unite offered 1,000 members free tickets and travel to London to those that needed it, amid fears the event would lead to financial losses for the party.

Days before the event, prices were slashed from £35 to £10 and the party announced that the Grammy award-winning band Clean Bandit would headline the event at White Hart Lane recreation ground on Saturday.

On Wednesday Theresa May had joked about the festival, playing on the fact that band the Magic Numbers were making an appearance. “Just about sums them up,” she said.

David Lammy, who spoke on the main stage, tweeted: “And they said they wouldn’t come ... Never mind the mendacious haters. We’re taking our country back!”

The shadow chancellor, John McDonnell, said the event showed “a movement on the march”.

Some attendees also praised the event. “Politicians should start realising that youth engagement is this. Corbyn spoke during 30 minutes. The rest of the day has been music, food and different debates. Young people is the future of our democracies, and without their engagement, democracy is in danger,” tweeted one.

A Labour party spokesman said the event had brought people together from all walks of life to discuss how society could be changed for the better.

He said: “We’re ambitious because for too long politics has been like a private members’ club, shutting out the people whose lives are most affected by decisions made in Westminster. We want to develop new and innovative ways to open up politics to a wider audience.”