Drummer Nick Mason says the recent Pink Floyd reunion that saw him and David Gilmour joining Roger Waters onstage was quite spontaneous in many ways. He also hopes that Gilmour will be open for a more substantial Floyd reunion in the future.

The stickman admitted he was surprised to see Waters and Gilmour rehearsing 'Comfortably Numb' during soundcheck when he arrived at London's O2 arena last Wednesday, May 11. "It hadn't ever been quite finalized," explains Mason to Rolling Stone magazine. "So, it was very nice to get there and see that [David] was there."

Mason reveals that the three ate dinner together backstage before the show. "We were all just a little bit nervous, because it was a pre-show moment so it wasn't that sort of totally relaxed, 'Let's all chat about everything'."

The drummer watched from the audience as Waters and Gilmour performed 'Comfortably Numb,' and then joined the pair onstage with a tambourine for the closing number, 'Outside the Wall.' "Incredibly, it's just three old blokes getting together for a moment, really odd," remarks Mason. "But if that's what people like then, that's great."

Meanwhile, Mason says that it's Gilmour's reluctance that's preventing a further, more substantial Floyd reunion. "I think particularly at the moment David has other issues to worry about," Mason explains. "But also people change from when they are interested in doing something to when they're not. I think that we will just have to wait quietly to see if Dave ever does come around to it. I think there is an outside possibility even if it's, you know, another Live 8."

Watch Nick Mason, David Gilmour and Roger Waters Performing 'Outside the Wall'