America's biggest rock band of the 1970s, Aerosmith announced Tuesday that they canceled the first two months of their gigs as the band's lead singer Steven Tyler entered rehab after a relapse.

The group known for hits including "Dream On" and "Walk This Way" plans to take the stage at the Park MGM hotel starting in September, according to a statement on Twitter.

Tyler, 74, has been open about past struggles with substance abuse, which had caused tension with his bandmates. In 2009, Tyler told People magazine he was receiving treatment for pain management and an addiction to prescription painkillers resulting from 10 years of performance injuries.

The band's statement on Tuesday said the singer had "worked on his sobriety for many years" but recently relapsed following foot surgery "and the necessity of pain management."

Tyler "voluntarily entered a treatment program to concentrate on his health and recovery," the statement said.

"We are devastated that we have inconvenienced so many of you," the band added. "Thank you for your understanding and for your support for Steven during this time."