Jo Whiley: You join me now with U2 in the BBC Rock Garden. What was it like when you arrived here today, because everyone's been talking about the feeling that you get when you arrive here. Edge?

Edge: It was actually seeing the logo because now, of couse, it's an icon. Just coming around the bend from the entrance into Hyde Park was the logo, just that chill. It was amazing, great feeling.

Jo Whiley: People saying their heart has been pounding.

Adam: It's fantastic that it's in the city, you know, that the city has let the park be used for it, because when it was out at Wembley, like last time ,it was kind of a different thing, but the city's really involved.

Jo Whiley: Yeah, I mean just as you arrive here thousands and thousands of people all heading here, buses, people cheering, it's quite immense. Bit different to last time that you played here. Go on, tell us about your entrance.

Larry: The entrance last time, was on the er... was on Noel Edmonds' chopper. And, er, I just couldn't help thinking of the headline,'U2 go down on Noel Edmonds's Chopper'. It was just one of those moments, but no, it's obviously very different 20 years later. Playing with Paul McCartney. Having that opportunity, something that for me personally, I just... It's like unimaginable. It's like goosebumps. It's like... (bows down, I'm not worthy posing!) and all of that.

Jo Whiley: When we heard the rehearsals that you were doing this with Paul McCartney, everyone just went rushing to the stage. How'd it go in rehearsals?

Bono: Pretty good.

Jo Whiley: Don't look at me like that!

Bono: No, no, no, it went really great. The song, this is a Beatles' seminal album. Sgt. Pepper's. This is a song he has never played. Ever. Which is the most remarkable thing. The Beatles never played this. They only ever did it once in the studio, that's what you hear at the start of the album. He did the coda at the end of the album, I think, before, but this, the actual Sgt. Pepper's Lonely Hearts club is the first time's he's performed it, so it's kind of freaking him out. I think he's realising how good a song it is partly, but it's very, it's very special. That album represents not just the Beatles, but the best of the Sixties, the best of what happened here in Britain and around the world, this idea that, you know, pop music, rock and roll music meets fashion meets politics, the possibilities of the future. It was a very optimistic moment. I think it's a good way to kick it off.

Jo Whiley: People that are criticising the event today are saying that a concert isn't going to change anything, it's not going to affect Africa that much. That's got to happen from within Africa themselves. So what does it mean to you, this event that's happening?

Bono: The rock stars, the hip hop stars can't change anything but our audience really can, because they are the people who put in and out of office the politicians, who really will have to change everything. Africa is, yes, it's got it's own problems to deal with, and it's taking them on, but countries that are dealing with corruption, are dealing with, you know, their problems. We should be right behind them with buckets more aid, and that's what this is all about, and no-one wants to redecorate presidential palaces here, you know. We're 50 billion dollars is the curse for global development. We can get it by the end of the week if enough people jump up and down about it. I'm not asking you to put your hand in your pocket, but we are asking people to put their fist in the air.

Edge: I think to add to that, people said the same thing about the first Live Aid. They said it won't make any difference and, you know, in terms of changing Africa, it made a small difference, but a significant difference. But I think if you just look at the impact that that concert, the first Live Aid, had on people's perception of justice issues, even the fact that Gordon Brown and Tony Blair both saw that first concert and we have now got to the point where it's just a given that it's moved on now. It's not about charity it's about justice. That in itself, just expresses. And I think if we can look back in another 20 years, we will, you know, we will be seeing the same kind of quantum shift, so I think it does really...

Jo Whiley: You can have a bit of fun on stage as well. You're looking forward to a great performance. Look at you, you're so laid back and so serious at the moment. It's going to be a good day

Bono: It's going to be... throw up.

Jo Whiley: Are you feeling sick, nervous?

Bono: Are you joking? It's a, it's the molecules of the air around here are vibrating a little faster than normal.

Jo Whiley: OK. Have a good show.

Bono: Thank you.

Jo Whiley: Thanks for talking to us. Bye bye. Get yourself off there.

[Bono pretends (complete with sound effects!) to be sick.]

(c) 2005 BBC