The British band recently announced they are reforming and tickets for their tour sold out in minutes.
Gallagher admitted to UK newspaper Daily Star: 'We'd known for a while and were sworn to secrecy. It's great for the fans and for them and a nice feeling just to see them together after so long.
'I love them as friends and as a band.'
However Gallagher also admitted he thinks the new X Factor panel needs a shake-up already.
He said: 'They should bring Simon Cowell back. It can't be a coincidence that the ratings have gone down just when he left.'