The 55-year-old star is back recording with singer-and-rapper Astro who joined Ali and keyboard player Mickey Virtue in January 2014 to reform as UB40.
Astro quit the other incarnation of UB40 - comprised of original musicians but with Ali's brother Duncan Campbell on vocals - after becoming disillusioned with their musical direction following the release of their country album 'Getting Over the Storm' saying it wasn't ''something he wanted to be a part of''.
Ali is thrilled to be working with Astro again and has promised fans they will be performing pure reggae when they head out on tour to perform with the classic UB40 hits being sung by the legendary vocalists who recorded them.
Talking about his reunion with Astro, the 'Red Red Wine' hitmaker said: ''Basically, after UB40 the oldsters made a country album which was a total slap in the face to me, to the fans and to Astro, he came back with me and Mickey - who left with me when I left nearly six years ago now.
''Astro had left and asked if he could join with me, I said, 'Yes.' So we did our first show at the IndigO2 in London in December and the reaction was so good we thought, 'F**k it. Let's get back together again.' We call ourselves UB40. We're back flying the flag for reggae again.''
Ali has also criticised his former band - which also includes his other brother Robin Campbell - for touring under their original name but not stating that he has been replaced as the singer.
The 'Can't Help Falling in Love' singer - who left the group in acrimonious circumstances in 2008 - told BANG Showbiz: ''All along the line I've been saying, 'Its Ali Campbell's UB40', or 'The Legendary Voice of UB40 Ali Campbell'. So that people knew who they were getting. Now, UB40 the old boys haven't done that once in six years; they haven't said, 'Not original line-up.'
Ali is currently putting the finishing touches to a new album with Astro and Mickey and he can't wait for people to hear it because it is a classic sounding UB40 reggae record.
Talking about the album, he revealed: ''The new album is 100 percent reggae, I know the fans are going to love it because it sounds like a UB40 LP ... That'll be out soon on Cooking Vinyl.''
UB4O - Ali, Astro and Mickey - will be touring the UK in December with dates in Birmingham on December 19, London December 20 and Manchester December 21. For tickets and information go to Kililive.com.
She's swapped the studio for a film set with new Netflix series.
Ed Sheeran performed a spectacular set on the Pyramid Stage on Sunday.
Viral video ties in 'GoT' soundbites to the lyrics of Gloria Gaynor classic.
Here are a few of the best moments over the Glastonbury weekend.
The wrestling series hit the streaming service earlier this week.
The Marvel Studios head was blunt in his answer.