The soul veteran underwent knee surgery last month (Jan17) and had hoped to be back on his feet in time for the start of his All the Hits Tour with special guest Mariah in Baltimore, Maryland on 15 March (17).
However, it was rumoured Lionel had suffered a setback in his recovery, and now he has confirmed the problem with his knee will take a little longer than expected to fully heal.
As such, Lionel has postponed the trek until the summer (17).
"When you have been performing as long as I have it takes a toll on your body," the 67-year-old admitted in a statement issued to People.com.
"Unfortunately my recovery from a knee procedure will not have me 100 per cent ready to start the tour next month. I don't want to disappoint my fans and I look forward to being back on stage so we can all be 'Dancing on the Ceiling' together again."
New dates will be announced next week (begs27Feb17) and tickets for the delayed gigs will be honoured for the rescheduled shows.
Mariah has yet to comment on the postponed tour, which had been set to wrap in Fort Lauderdale, Florida on 27 May (17).