Hard at work in their Dublin studio on the upcoming release of their 12th studio album, tentatively titled No Line On The Horizon, U2 rocker Bono (aka Paul Hewson) has reportedly been ordered to slim down in order to get prepared for the band’s upcoming world tour.

A source says the “Desire” rockers are determined to be in peak physical shape once they hit the road in early 2009. “U2 have an album coming out around January,” says a source close to the band. “And then the band is going on another world tour in March and April – so the boys have been told to start exercising all the summer weight off.”

U2 recently got in a spot of trouble when a nearby neighbour recorded tracks on his mobile phone, after Bono was caught out playing them loudly from his villa in the south of France.

The fan soon uploaded the new single “Sexy Boots” online – the band later forcing sites to remove the content.