U2 guitarist The Edge has defended the bands elaborate stage set up and the carbon foot print the bands tour is causing.
The band are currently taking to the stage surrounded by three steel structures which cost between £15m and £20m each, offering a largely unobstructed view of the rock quartet.
The "claw" stage enabled an estimated 88,000 fans at Wembley to watch U2 on Friday.
Speaking to BBC 6 Music, The Edge said: "We're spending the money on our fans, I don't think there's a better thing you could spend it on."
Talking Heads frontman David Byrne however was not impressed. He slammed the band on his blog and said that given U2's work in Africa their world tour costs were "excessive".
While on tour in Europe Byrne wrote: "$40 million to build the stage and, having done the math, we estimate 200 semi trucks crisscrossing Europe for the duration.
When asked whether the Irish rock veterans were stung by the criticism they received, The Edge said, "I think anybody that's touring is going to have a carbon footprint.
"I think it's probably unfair to single out rock 'n' roll. There's many other things that are in the same category but as it happens we have a programme to offset whatever carbon footprint we have."
U2 Rock Wembley Stadium:
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