Music stars from every decade of Queen Elizabeth's 60-year reign, ranging from Shirley Bassey to Jessie J, will perform at a concert outside Buckingham Palace in June to celebrate the British monarch's diamond jubilee.

They have a hard act to follow after Brian May, the guitarist from superstar band Queen, performed an electric version of God Save the Queen on the roof of the palace during a similar concert 10 years ago, for the golden jubilee.

Gary Barlow of the band Take That, who is organising the concert, acknowledged it would be difficult to create a moment as memorable as May's rooftop solo.

We need to come up with something newer and better. Maybe we'll fly someone in, Barlow told a news conference in the Throne Room at Buckingham Palace on Tuesday.

Elton John, who is among the line-up, will face the additional challenge of living up to his tear-jerking rendition of Candle in the Wind at the funeral of Princess Diana in 1997 -- one of the defining moments of his long career.

It's going to be fun, he said in a video to present the concert, shown at the news conference.

Paul McCartney, Tom Jones and Annie Lennox are also among the veteran rock and pop stars who will take to the stage, while English tenor Alfie Boe and Chinese pianist Lang Lang will bring a classical touch.

Bassey, whose career in Britain took off in the 1950s and who later found international fame by singing James Bond film theme songs, will represent the older generation along with Cliff Richard, whose enduring appeal to a fanatical female fan base has kept him on the British A-list for over five decades.

Among the younger acts will be Jessie J, who scored her second UK number one hit with the song Domino last month, and the boy band JLS, who rose to fame by competing in the popular television show The X Factor.

PICNIC AT THE PALACE

The Queen has seen the musical line-up and she is entirely content and happy, said a Buckingham Palace spokeswoman.

Barlow hinted at where the 85-year-old monarch's preferences might lie in his response to a question about whether she would attend the 2-1/2 hour concert from start to finish.

She chooses when she comes and goes so she'll probably be heading out when I start to sing and heading back when Cliff starts to sing, he said.

Barlow also said that the queen's grandsons Princes William and Harry had both put in some requests for particular artists, but he did not say who they were.

The concert will take place on June 4, on an unusual circular stage built around the huge memorial to Queen Victoria that stands in front of the Buckingham Palace gates.

Victoria, who was queen from 1837 to 1901, is the only monarch in British history to have reigned for longer than Queen Elizabeth.

The circular stage is the work of Mark Fisher, who has previously designed sets for rock bands of the calibre of Pink Floyd and the Rolling Stones.

A lucky 10,000 guests from across the United Kingdom, chosen at random through an online and postal ballot, will receive free tickets for the concert which they will enjoy from a circular arena built around the stage.

Applications for tickets can be made through the website www.bbc.co.uk/diamondjubilee from Tuesday until March 2.

Before the concert, ticket-holders will be invited to a jubilee picnic in the garden of Buckingham Palace.