The band's former guitarist was a surprise guest at the 'Changingman' singer's show at London's Relentless Garage where he joined his pal in a rendition of the group's 2005 song 'Mucky Fingers', as well as 'Echoes Round The Sun' - which was recorded by Noel and Paul for his last LP '22 Dreams'.
One gig goer said: "We couldn't believe it when Noel walked out, it looked like they were having a great time together."
However, it is unlikely that the pair went out partying afterwards.
Noel - who is expecting his second child with long-term partner Sara MacDonald - has revealed he had to ban himself from drinking with his friend because he is such "a nightmare".
The 42-year-old musician admitted on British radio station Talk Sport: "I guess Weller's my oldest friend, and I don't mean the fact that he's, like, 50. I mean the fact that I've known him for a long time, I've known him for about 12 years.
"There's an unwritten law that I never go out with Paul Weller, he's a nightmare. He's hardcore - if you go out with him, if you come home at all, there's bumps and bruises. There's been scuffles in the street and you've probably fallen out with him."