The singer’s spokesperson has lashed out at the band for not being “magnanimous”.
George Shelley is out of Union J, with both sides openly blaming each other for the split.
“It was a mutual decision for George to leave Union J so he could focus on his broadcasting and acting career,” Shelley’s representative told Digital Spy.
“He is an utterly charming and hardworking individual – not a diva in the slightest.
“The fact of the matter is that the other members of Union J are simply jealous he has achieved the start of an exciting new career and they have not.
“George had agreed to be totally magnanimous towards them, but unfortunately this has not been reciprocated.”
Union J were quick to his back at their former bandmate – who joined the group when both acts auditioned for the X Factor in 2012.
Jaymi Hensley admitted to The Sun that he feels “bitter” about the divide.
“It’s heart-breaking. I spoke to him the other day and I said I’m heartbroken over this. I am absolutely devastated,” he added.
“It brings us down. When you turn up to something and the other person can’t be there, or they are turning up late.
“That makes you not love the project. One negative view can ruin it for everyone.”
Last month, Shelley opened up about his sexuality to put an end to internet speculation, after he appeared on I’m a Celebrity… Get Me Out of Here!.
He said in a video: “I’ve been reading a lot of speculation online as to whether I’m, straight, gay or bi.
“It’s all these labels and it’s a little bit old-fashioned and this is why I’m not going to label it myself,” he explained.
“I’ve had girlfriends that I’ve loved, in amazing periods of my life, but I’ve also had boyfriends.”
“I want you to know that whether I decide to be with a girl next or be with a guy next it’s because I love them.”