Kasabian frontman Tom Meighan has left the band to focus on dealing with “personal issues”.
A statement from the Brit Award-winning rock group from Leicester said the 39-year-old wants to concentrate on “getting his life back on track”.
His departure leaves guitarist Serge Pizzorno and bassist Chris Edwards as the only remaining founding members, with current drummer Ian Matthews joining the group in 2004.
A statement on behalf of the group said: “Kasabian have announced today that Tom Meighan is stepping down from the band by mutual consent.
“Tom has struggled with personal issues that have affected his behaviour for quite some time and now wants to concentrate all his energies on getting his life back on track.
“We will not be commenting further.”
It is not clear whether Kasabian will seek to replace Meighan as lead vocalist.
Meighan is known for his on-stage antics and outspoken opinions of other musicians including Julian Casablancas, Pete Doherty and Justin Timberlake.
He is also a vocal critic of Simon Cowell’s reality TV shows including the X Factor, claiming they have a negative effect on people’s mental health.
In 2012, he told The Sun that he had suffered a “meltdown” while Kasabian were on tour in the US that year.
He said: “I had a meltdown. Not a complete breakdown but I just lost it through the realisation of what was going on in my life.
“I went a bit mad for a couple of days. I panicked. I’ve never had that before. And I was at breaking point.”
In a 2017 interview with Q Magazine, he said he had “lost himself” the previous year, in which he moved out of the home he shared with his long-term girlfriend and daughter.
Referring to Leicester City’s Premier League win, he said: “2016 was great for Serge, great for Leicester City, s*** for me.
“I had to sort my head out. My attitude. Stuff I was doing. People I was associating with. Not bad people. I was the one that was bad, I was in the haze.”
He added: “Sometimes life throws s*** at you and I didn’t deal with it very well. I was making myself ill, I ain’t gonna lie, my mind was jolted.
“It might have been a build up from years and years. I wasn’t taking responsibility and it affected everyone around me, horrendous.”
Last month, Meighan revealed that Kasabian were back together after a hiatus and working on their first new material since For Crying Out Loud in 2017.
Those sessions came after Pizzorno used the band’s break to release a well-received solo album under the moniker The SLP.
Kasabian formed in 1997 before breaking through with 2006’s Empire and 2009’s West Ryder Pauper Lunatic Asylum, which featured a string of hits including Underdog and Fire.
They headlined the Sunday night of Glastonbury in 2014 to generally positive reviews.
In 2017, they scored their fifth straight number one record with For Crying Out Loud.
Only their self-titled debut released in 2004 failed to reach number one, peaking at number four in the UK.