U2 together until we die - Bono
U2 frontman Bono believes the chart-topping band will stick together until they die.
The quartet - still going strong 35 years after they formed - are "unemployable" beyond their roles in the band, the singer said.
He and guitarist The Edge are attending the Toronto Film Festival to launch a new documentary, From The Sky Down, about the making of their 20-year-old album Achtung Baby.
Bono said the group are united by "a kind of belligerent respect" for each other. He added: "We're unemployable, you know, it's like the priesthood, there's only one way out, in a coffin."
The film - made by director Davis Guggenheim - examines the making of the album in Berlin, Germany, which helped to reinvent the band. But Bono said he found it difficult to trawl through the past.
"I found it very hard to watch, to be honest with you. We're not very good at looking back at things. I mean Edge - when he put together our Best Of collections - forced me, actually had to physically force me, to listen to it before it went out."
"I'm just not interested in what we've done, I'm always more interested in what we're about to do. But you know, for this album, we made an exception."
The millionaire rock star said he is intrigued about why someone would want to see how the LP was assembled.
"It's like a load of songs and they turned out pretty good in the end, and this is a film about how they nearly didn't. I don't know why anyone would watch it, I really don't," Bono said.
The Edge - whose real name is Dave Evans - added: "I think it's not a movie about us, per se, it's really about how bands function, or in this case, don't function."