Nicholson, who split from the Sheffield rockers in 2006, formed a new group earlier this year with members of Reverend and the Makers, Babyshambles' Drew McConnell and rapper Lowkey.
He also confirmed that former bandmate Matt Helders would be playing drums for the project.
The band are currently working on an album at London's Dean Street Studios and are expected to tour later this year.
Talking about his new group's sound, he told NME: "Mongrel is something you can't pigeonhole - there's dub tunes, reggae tunes and dancey tunes."
When asked about the period immediately after his departure from the Arctic Monkeys, Nicholson said: "I thought I'd keep my head down, grow up a bit and come back twice as strong.
"Muhammad Ali lost his title and four years later he came back! I could have got a deal as 'Andy Nicholson', but I wanted to do what's right for me."
When asked about his relationship with his old band, he added: "We've put what happened behind us and moved on.
"We've got the same relationship now that we had when we were 16 and drinking on street corners, running away from policemen while smoking the herb."