The 61-year-old co-founded the band almost 50 years ago, when he posted an advert on a school notice board, in Clontarf’s Mount Temple Comprehensive.
The self-taught drummer, who is renowned for his high-octane style, has said that decades of concerts have taken a toll and if U2 tour next year, it will likely be without him.
The famously private musician, who his bandmate Adam Clayton has described as the “bulls--- detector”, told the Washington Post that he needs surgery to continue playing.
In the wide-ranging interview, U2 frontman Bono said the best albums that the band has produced always led to infighting, as they pushed each other and fought to get their own ideas across.
As part of the extensive interview, which was Mullen’s first interview in seven years, he said the dynamics of the band have shifted over the years.
Earlier on U2 followed the Communist Party committee system, or “Politburo”, when it came to deciding on the best course of action.
Mullen argued that nowadays the band very much has one leader, but he still follows his own path.
"You only do this if you’re having the best time,” he said.
“And not everyone is going to make it because the price is so high. So I think the challenge is for more generosity. More openness to the process. I am autonomous and I value my autonomy. I don’t sing from the same hymn sheet. I don’t pray to the same version of God. So everyone has their limits. And you only do this if it is a great time you’re having, you know?”
U2 will be presented with the highly the prestigious Kennedy Centre Honours on December 28, for their contribution to the arts.
The band has been performing since in 1976, but frontman Bono admitted that they have close to breaking up a number of times.
"We come close to breaking up much more often than you’d think,” he said.
“Usually after the really good albums, because they cost you in personal relationships because you’re pushing each other and get really at your elastic limit.”
Earlier this month, Bono released his highly-anticipated memoir Surrender: 40 Songs, One Story.
He has no plans to do a solo album and said the band has almost finished a new album of original tracks, which will be called Songs of Ascent,however, they have not decided when or if it will be released.
Bono said the tracks on the album are more high-tempo than some of their recent releases and they are driven by the Edge’s virtuoso guitar playing.
He said the group still has something to offer.
"I have a feeling that we have something. That if we can distill it on these next sessions, this unreasonable guitar record that we all want to make actually, I just feel there’s a moment,” he added.
"I don’t know if you can capture people for a whole album. But what if it was just an EP or just one song that could burst through? We don’t need it on the pop charts. We don’t. But we need people to pass it around. I think we do want that.”