Shortly before Christmas, Peter Cetera hinted at a big announcement regarding his possible involvement when Chicago are inducted into the Rock and Roll Hall of Fame in April. Today (Jan. 5), he offered to join them for one of their biggest hits. Cetera has not performed with the group since leaving in 1985.

In an open letter that he posted on his website, Cetera, who had previously "emphatically declined" to rejoin the band that night, suggested that he play "25 or 6 to 4" on bass during the finale. Then he raised the ante by calling for several other former members, including keyboardist Bill Champlin, who was in the band from 1981-2009, and Cetera's brother Kenny, a percussionist who toured with them in 1984-85, to be onstage with them. He says he made the offer in the hopes that it would go "a long way towards healing old wounds and showing solidarity on that night."

The full text reads as follows:

Hello Everyone! I’ve just sent this mail to everyone involved. Hopefully it will answer all the questions concerning my participation in the Hall of Fame induction..Thanks

Hello Robert, Danny, Lee, Walter, and James. I’m sending this to you and Danny since yours are the only email addresses I have. Please forward this to everyone.

First off, congratulations all around on this long overdue honor. While our fans believe we should have been inducted years ago, they find it harder to believe that we haven’t even been nominated in all that time. Oh well, we are now!

All the credit goes to those who voted for us in overwhelming numbers during the recent poll. They alone deserve our thanks for finally making this happen.

I know we all look forward to speaking that evening and I’m sure we all wish that Terry was there to join us. That can’t happen unfortunately, but I have one thing that can.

As a finale, we can walk onstage together one last time as a group, I’ll strap on the bass, and we can do "25 or 6 to 4" in the key of E. I believe it would make for one fantastic Hall of Fame moment and satisfy those who have always wanted some sort of reunion.

Along with your current members, I would also like us to invite past members Laudir de Oliveira, Donnie Dacus, Kenny Cetera, Chris Pinnick, and Bill Champlin to join us up there as well on the song. They’ve all contributed to the legacy of the group and I think this would be a fitting way to honor them.

In the end, this should go a long way towards healing old wounds and showing solidarity on that night. At least I hope so!

See you all in Brooklyn, Peter

Last month, it was announced that Chicago would be inducted into the Hall after winning the official fan vote. The other members of the Hall's Class of 2016 are Cheap Trick, Deep Purple, the Steve Miller Band and N.W.A.

2015's Nastiest Rock Feuds

See the Top 100 Rock Albums of the ‘70s