According to The Sun, the Oasis singer and Allen thoroughly enjoyed their 11-hour Virgin Atlantic flight.
The party began for the stars before takeoff, at the lounge in London’s Heathrow airport. Once on board, the artists continued to party with glasses of champagne.
Despite warnings from Virgin Atlantic staff to respect the other passengers, the two stars carried on as if they were the only people in the world. One passenger revealed, "They were already well-oiled by the time they came on board. There is obviously a different set of rules for celebrities."
Gallagher, his band Oasis and Allen were on their way to perform at the Fuji Rocks Festival from July 26-26.