Motown icon Stevie Wonder, rapper Snoop Dogg and Irish rockers U2 will be among star attractions at this year's Glastonbury music festival, organisers said Thursday.

Also included in the line-up are British electro-pioneers Pet Shop Boys, American quartet Vampire Weekend and Mercury Prize nominees Florence and the Machine.

U2 and Wonder will be making their debut at the 40th anniversary of the festival which will be held at Worthy Farm in Somerset, southwest England, on June 23-27. The Irish band's appearance was already announced last November.

English rockers Muse, who won two awards from leading British music magazine NME in February, occupy the prestigious Saturday night headline spot having previously played the festival in 2004.

The booking of Snoop Dogg revisits the controversial, but ultimately successful, experiment of 2008 when fellow rapper Jay-Z played the Saturday headline spot.

Festival founder Michael Eavis dismissed any concerns about the rapper?s reputation, telling the Guardian newspaper: "Jay-Z worked so well, when we heard it was a possibility that Snoop Dogg could do it we went to work.

"We never pass judgment on the people who play here; we hire them for their musical ability. We are only interested in their music and what they will bring to the festival. We never compromise on that."

The sold-out festival has its roots in the hippy movement but now embraces all types of music and performing arts.

Glastonbury has become famous almost as much for its weather as the music in recent years: in 2005 and 2007 the site was turned into a mudbath by torrential rain, although a new drainage system has improved things for festival-goers.

Last year's event climaxed with sets by Bruce Springsteen and Neil Young, as well as Britpop kings Blur, although the whole festival was clouded by the death of Michael Jackson just as it opened.

Tickets for the 2010 festival sold out within 24 hours in October. Some 177,500 people will be at the event.