Sir Tom Jones has accused the BBC of "sub-standard behaviour" over his axing from The Voice.
The singer said he was told only on Thursday that he would not be returning to the reality singing contest as a coach - just 24 hours before the new line-up was announced.
The disgruntled music veteran said he was ditched "with no consultation or conversation of any kind".
It was announced yesterday that the Welsh star, who has been a coach on the show since it launched, and singer Rita Ora, who earlier announced she was quitting, are to be replaced by Paloma Faith and Boy George.
In a post on his Facebook page, Sir Tom said last night: "In good faith, as part of the team, I'd put the time in my schedule to be involved in series 5, as I've done so for the last 4 years.
"I've supported the show and the BBC since the beginning. I was told yesterday, with no consultation or conversation of any kind, that I would not be returning. Having been through plenty of transformations throughout the years, I support and admire creative change.
"But being informed, as a matter of duty and respect, is an important part of creative relationships. This sub-standard behaviour from the executives is very disappointing.
"I will always admire the courage of the performers who participate in the show, as well as all the production staff who worked tirelessly to make a great family viewing experience for the audience at home. I wish the show well."
Paloma Faith and Boy George will join the show alongside returning coaches Will.i.am and Ricky Wilson for the fifth series of the BBC One competition.
Faith, who collaborated with Jones on the track God Only Knows, said: "I'm really excited about working with creative people who are there not just to be great singers, but also innovative personalities and performers.
"I'm really looking forward to getting my teeth into something that cultivates the talents of another person and takes the focus off myself for a bit."
Culture Club frontman George, real name is George Alan O'Dowd, said: "I'm thrilled and excited to be a coach on The Voice UK. I'm a huge fan of the show and have watched and engaged with it from series one.
"If I can help someone to win I will be delighted. What a wonderful opportunity to share my experiences and help someone move forward with their musical career. I can't wait to sit in that chair."
Sir Tom, 75, who had hits with It's Not Unusual, Delilah and Sex Bomb, mentored Leanne Mitchell to win the first series of The Voice.
Filming on the fifth series is to begin at Media City in Salford, Manchester, in September.
Emma Willis and Marvin Humes will return to host the show, which will air on screens in January 2016.
A BBC spokeswoman said last night: "The final decision on the coaches' line-up for series 5 of The Voice was only taken on Wednesday and Tom's team was informed early yesterday morning.
"We then announced it to the press so that it didn't leak. This has been the same every year and no role was ever promised."