The war of words between UB40 and former lead singer Ali Campbell intensified yesterday, as the band prepared to head off on a final tour as an eight-piece.

On Thursday, Campbell, UB40's singer, announced he was leaving the band, blaming difficulties with management as his reason. The band, however, deny this and claim the real reason is Campbell's desire to concentrate on his solo career.

Yesterday they said that they had bent over backwards to accommodate Campbell's wishes, supporting his promotion of the album, Running Free.

UB40's new album, 24/7, was due to be released before Christmas and is now due in May, proof - say the band - that they were fully behind Campbell's solo project.

In the statement the band says: "It is not normal practice for UB40 to discuss their affairs in public or through the media, but . . . UB40 would like to clarify incorrect and misleading statements circulating in the media and to their fans.

"Ali Campbell claims that he was forced to resign from UB40 due to issues with the band's management and was shocked at the official statement issued by UB40.

"He further claims that the real reasons he left the band were due to 'bad administrative practices and that for the last five years he had been kept in the dark over the band's finances.'

"UB40 would like to confirm that Ali Campbell resigned from the band after a meeting with the other seven band members on Thursday evening (January 24) at their studio in Birmingham. The seven band members, including Campbell's brother Robin, asked Ali to clarify if he was going to remain as their lead singer. Ali responded by saying that he was leaving the band after completing UB40 tour dates in February 2008.

"Ali was not at any time, forced to resign by any of the other band members or management acting on behalf of the band.

"The band would like to clarify that they do not have artist management and that all decisions relating to UB40 as a band, both past and present, in their 30-year career, have always been by a democratic process of all eight members since the band formed. A decisionmaking process which Ali Campbell has actively participated in and been a fully paid up member."

Yesterday afternoon, the seven members of UB40 were locked in a crisis meeting and Campbell was unwilling to comment on the situation.

His spokesman told The Birmingham Post: "I think it is best if they sort it out between themselves now rather than in the public domain."

On Wednesday the band fly to New Zealand for the first date of their last tour. Campbell has vowed to honour these commitments as he works out his notice with the band he has been fronting for almost 30 years.

However, UB40 is in no doubt why Campbell chose to leave.

They say: "Ali made a very simple decision, he chose to pursue and put his solo career over and above continuing to work with UB40 after February 2008, it's as simple as that.

"He even engaged a solicitor to inform the band of his wishes, several weeks prior to their meeting, which, given their 30-year career together, speaks volumes."

They say that all decisions within UB40 are made by the band, not management or record label: "It's disappointing that Ali seems to have forgotten that he has at all times been involved in this process.

"It's also somewhat puzzling and ironic that the other seven band members, don't have any issues over any decisions that the band have made together and that it has taken Ali over five years to only now voice his concerns over such important matters and claims."

The band fully supported Ali in his solo project, they say. Robin Campbell sang on Running Free and appeared in a video and Brian Travers was responsible for writing the lyrics to all the original tracks on the album.

The band said: "UB40 had several meetings in 2007 in which Ali was present and in which the other seven members agreed, by their normal democratic process, to postpone the release of the UB40 studio album 24/7 to allow Ali plenty of time to release and promote his album so that both albums would not clash.

"At all times the band have unselfishly fully supported this decision and allowed Ali to promote his album throughout last year and again in media interviews on the band's last UK tour in December. UB40 had a sold out British Tour in December 2007, in which their new album 24/7 was originally scheduled to be released and promoted at these shows, Ali was allowed to promote his album and utilise this opportunity to a captive audience.

The spokesman added: "The band feel very disappointed that having given Ali their full support throughout 2007 with his solo album that he was unable to commit to the promotion of the new studio album and the band's tour dates, this was a complete contradiction to previous statements."