Prince William will marry Kate Middleton on Friday, April 29 next year at Westminster Abbey, St James’s Palace announced today.

Downing Street said the wedding day would be a public holiday.

And the wedding – including the costs of the church service, music, flowers, decorations reception and honeymoon — will be paid for by the royal family and the Middleton family.

The public will pay for associated costs like security.

Jamie Lowther-Pinkerton, private secretary to Prince William, said the couple chose Westminster Abbey for its “staggering beauty”, 1,000-year royal history and intimacy despite its size.

The announcement came as William’s father the Prince of Wales was congratulated on the forthcoming wedding while chatting with cheering schoolchildren and their parents.

Charles spent 15 minutes talking to a crowd of flag-waving youngsters outside Bradford’s City Hall as he arrived for a visit to celebrate the Campaign for Wool. Mr Lowther-Pinkerton told reporters in a briefing at St James’s Palace: “The venue has long associations with the royal family – it is in many ways the royal family’s church – and of course with Prince William personally.

“For Miss Middleton, the associations she has with the Abbey are quite simply the same as any British person would have for such a glorious and holy place.” Mr Lowther-Pinkerton said those planning the nuptials were very conscious of Britain’s precarious finances.

“All parties involved in the wedding, not least Prince William and Miss Middleton, want to ensure that a balance is struck between an enjoyable day and the current economic situation,” he said.

“To that end the royal family and the Middleton family will pay for the wedding.”

He said this move drew directly from the precedent set by the Queen and the Duke of Edinburgh’s wedding in 1947 and Charles and Diana’s nuptials in 1981. Mr Lowther-Pinkerton said William and Miss Middleton were “completely over the moon” about their engagement.

“I’ve never seen two happier people,” he said. “They’re on Cloud Nine, like any other newly-engaged couple.

“They’re now getting stuck into organising their wedding. They are very much in charge of the arrangements for the big day.

“They’re giving us and the household office very firm direction indeed.”

The Very Rev Dr John Hall, Dean of Westminster, said: “First of all, how delighted we all are at their engagement and we look forward very much to all the detailed preparations for what will be an enormously happy and glorious event.

“Of course we are very pleased that they have decided to get married at Westminster Abbey.”

Prime Minister David Cameron said: “The wedding of Kate and William will be a happy and momentous occasion.

“We want to mark the day as one of national celebration. A public holiday will ensure the most people possible will have a chance to celebrate on the day.

“The costs of the wedding itself will be met by the Royal Household, with Government meeting any wider security or transport related costs.”

By David Burrows