Lily Allen 'will reveal dynamite details of boozy flight sex with Liam Gallagher'

Lily Allen at the Diversity in Media Awards, 2017. Photo / Getty Images

Lily Allen, 32, reportedly will divulge the intimate details of her alleged sex session with Liam Gallagher, 45, during an 11-hour flight to Japan in 2009 in her tell-all book.

The pair were said to have toasted with champagne at Heathrow's Upper Class lounge before continuing their drinking antics on board the plane, The Sun reports.

It is claimed the explosive book will reveal how the musicians enjoyed a fling mid-air in first class as they made the journey to Japan's Fuji Rocks festival, said the Daily Mail.

Crew members allegedly scolded the randy rockers for their reportedly sexual antics on the long haul Virgin Atlantic flight.

The English singer, songwriter and musician Liam Gallagher in Bergen, 2017. Photo / Getty Images

"Everyone who read it was stunned as it's amazing stuff and could be dynamite."

The book is also said to revisit an awkward encounter when Lily was said to have ran into Liam and his then-wife Nicole.

"It was fairly soon after the flight, which had sparked gossip in pop circles. Lily made a beeline for Liam and Nicole and started chatting. But Nicole was not happy about it, as she had heard the gossip and it caused a few ructions between her and Liam." The source added to the publication.

The former Oasis singer married songstress Nicole Appleton in a romantic ceremony in February 2008, just 17 months before the alleged fling.

MailOnline has reached out to Lily Allen and Liam Gallagher's representatives for comment on this.

Liam and Nicole, who share 16-year-old Gene, went their separate ways for good when they were officially divorced in April 2014.

Lily Allen at the Diversity in Media Awards, 2017. Photo / Getty Images

The rocker also has another son, 18-year-old Lennon, who was welcomed into the world with his first wife Patsy Kensit.

The former flames were married in a romantic ceremony in April 1997 but they parted ways for good when they divorced in 2000.

While the musician sees his sons regularly, he confessed he has never met his two daughters Molly and Gemma. Liam has now found love again with his long-time ladylove Debbie Gwyther.