Aerosmith guitarist Joe Perry says estranged singer Steven Tyler's surprise guest appearance at his Joe Perry Project concert Tuesday night (Nov. 10) in New York "really didn't change anything in my mind" about the status of their band.

Tyler joined Perry and company for an encore rendition of Aerosmith's 'Walk This Way," before the song that "I want you to know that I'm not leaving Aerosmith."

Now, Perry tells Billboard.com that Tyler "never said he was leaving the band" but further explains that the singer "said he wanted two years off to do his other projects," which is where things become problematic. 

"Aerosmith wants to work," says Perry, who Tweeted earlier in the week that the band was "positively looking for a new singer to work with." He adds, "the band's been playing together for 40 years. It's a really powerful rock band, and I don't want to see it just go to waste and I don't think any of the other guys do, either. We're gonna work and we're gonna do something -- I'm not exactly sure what yet, but the band's too good to let it sit around. We're not going to wait for Steven." 

Perry says he's had one conference call during the past week with bandmates Brad Whitford, Tom Hamilton and Joey Kramer, but they have not made any firm decisions about anything -- including working with another singer while Tyler is pursuing his outside endeavors. "We're waiting for things to kind of settle down, and then we'll figure out what we're gonna do. Anything is possible," the guitarist says.

Perry also says that Tyler's appearance at Irving Plaza on Tuesday caught him completely by surprise. Tyler, he says, appeared backstage just as the Project was taking its encore break. "He was really the last person I expected," Perry recalls, "and then I saw him. He said, 'How ya doin'? What's going on? What songs are you playing -- anything good or what?' I said, 'Well, we've got a couple more to go...You want to come and sit in with the band?' and he said 'Yeah' and...[chose] 'Walk This Way.'"

"I was really blown away that he came to the show," says Perry, "but he showed up and was really anxious to come and sit in and play, so I figured, what the hell? He's been my partner for 40 years, and I figured I'd let him have some fun and...give the fans an extra treat."

As for spreading Internet rumors about Tyler's health, Perry says that the singer "came and went so fast I didn't even get a chance to check him out that much...We read the Tweets and the different bits of gossip here and there, but that's stuff you need to talk to Steven about."

Perry says the Project, meanwhile, will be on the road throughout the month and then plan to resume touring in late January, though he expects to be speaking to the other Aerosmith members in the near future about their potential plans. -billboard.com