Marching bands, a giant dragon puppet and circus acts will form part of a spectacular pageant to celebrate the Queen’s Platinum Jubilee.

Central London will come to life with colour, street theatre and dance in honour of the monarch’s long reign in what has been described as “something of a reopening ceremony for the United Kingdom”.

Organisers said the event, with a budget of between £10 and £15 million and involving participants from across the UK and parts of the Commonwealth, is expected to be one of the biggest celebratory events held for decades.

Details of the pageant, to be held on Sunday June 5 next year, were revealed at the official launch in London’s Victoria and Albert Museum on Tuesday.

On February 6 2022, the Queen will have reigned as monarch for 70 years, the first time a British sovereign will have reached such a landmark.

Throughout the year, the Queen and members of the royal family will travel around the country attending a range of events to mark the milestone, culminating with the Platinum Jubilee Weekend.

The four-day weekend will begin on the Thursday with Trooping the Colour, which will be staged in full for the first time since the pandemic, and a service of thanksgiving for the Queen’s reign will be held at St Paul’s Cathedral on the Saturday.

Sunday’s pageant will comprise of three acts, with the first seeing both serving troops and veterans take part in a march along The Mall in front of Buckingham Palace.

The second act, entitled Celebration, will feature a puppet dragon larger than a double-decker bus with a wingspan the width of The Mall.

Others taking part will include a trapeze artist suspended underneath a huge balloon printed with an image of the Queen, as well as acrobats and other performers.

The specially-written fairy story There Once Is A Queen by renowned author Sir Michael Morpurgo will be brought to life through artists on the day.

The pageant will have a nod to every decade of the Queen’s reign, and feature horses and corgis to reflect her passions.

Nicholas Coleridge, co-chairman of the pageant, said: “The Platinum Jubilee weekend is an opportunity for the country to emerge re-energised and renewed, expressing optimism and confidence.

“It will be something of a reopening ceremony for the United Kingdom, following a period of uncertainty and hardship, a catalysing moment of unity and fun.

“Through the fusion of ceremonial and pageantry with razzmatazz and festival, we intend to create a spectacle that is at once energising and memorable and a fitting tribute to the Queen.”

Details of the pageant’s third act, the finale, are being kept secret for now.

The pageant will be privately funded, organisers said, through a mix of corporate partners, business and individuals.

Adrian Evans, pageant master, said the celebration “has the capacity to raise the spirit of the nation”.

He added: “You’re doing something which is on such a grand scale, and it’s seen by so many people and so many people feel such a sense of warmth and admiration for the Queen that doing something for her feels like it’s a gift, not just to her but a gift to the nation as well.”

Asked if he is nervous at the prospect of organising such a large event, he said: “I wouldn’t be human if there wasn’t an element of nerves.

“It’s a massive stage – this is as big as it gets for an event director.

“It simply doesn’t get bigger.”

He said there would be a “sprinkling” of the Duke of Edinburgh’s presence throughout the day, including a reflection of “the way in which we imagine her and the Duke of Edinburgh in their sort of private existence”.

“He is a constant presence,” he added.

In one part of the event, the monarch and Philip will be represented through “Queen” and “King” costumes in a carnival-style representation of her coronation.

More than 250 costumes will feature in an imagination of the animal kingdom’s response to the news the princess was to become Queen while she was on tour with her husband in Kenya.

In response to a question as to whether the Duke and Duchess of Sussex would be attending, pageant chief executive Rosanna Machado, said: “As with all royal events Buckingham Palace don’t reveal details of which members of the royal family are attending until much nearer the time.

“So we will update you in due course.”