Close friends say Streisand, 76, is upset 32-year-old Gaga and her co-star and producer Bradley Cooper refused to create a cameo role for her, or accept any help behind the camera.
She has hit back by releasing a re-edit of the 1973 blockbuster featuring never-before-seen footage of her playing Evergreen on the guitar and a fresh twist on her final, haunting scene with co-star Kris Kristofferson.
It is already streaming live on Netflix and Streisand also reportedly plans a remastered version of her original soundtrack.
A friend of Streisand said yesterday: “She feels offended no one seemed to even want to acknowledge her, let alone take any advice.
“It’s as if she has been brushed aside by a new generation of artists who aren’t remotely interested in learning from a vastly experienced entertainer who’s achieved just about everything in showbusiness.”
Gaga – who won her first acting award in 2016 for TV series American Horror Story: Hotel – is also fuming.
A source said: “Gaga is angry and a little worried about the impact Barbra’s projects are going to have on hers.”
The Gaga reboot that hits UK cinemas in October is the fourth time A Star Is Born has been made.
The story of love between a rising female star and a fading male performer first hit movie screens in 1937.
There was a musical in 1954 then came the 1973 multi award-winning blockbuster.
Now Gaga aims to recreate that success with her reboot.
Her friend said: “Despite bad blood and ugly rumours, she is one hundred per cent confident her film will be a winner.”