Bono and his band, U2, are suing an ex-stylist for blackmailing them and for selling their personal belongings without asking them.

The band members are attempting to recover $6000 worth of souvenirs, including a Stetson cowboy hat, sweatshirt, trousers and earrings worn by Bono during the band's 1987 "Joshua Tree" world tour.

"You may have wealth and power, but when someone is trying to push us around and blackmail us and threaten us with books, at a certain point you have to say 'Stop right there'," Bono said.

Stylist Lola Cashman declared that "I am not a vindictive person, but it's my property and it is unfair that they are preventing me from auctioning it if I want to. We're all adults and I hope that there will be some sort of resolution."

Cashman, who worked for U2 in 1987, tried to sell the items a few years ago. Also, she published an unauthorised biography of U2 last year, titled Inside The Zoo, which claimed that Bono was obsessed with his weight and height.