The 67-year-old singer was due to team up with the 'We Belong Together' hitmaker for the 'All The Hits' tour next month, but they have had to push back the dates while Lionel recovers.
He told E! News: ''When you have been performing as long as I have, it takes a toll on your body. 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.''
A representative added: ''The tour will be postponed until the summer. New dates to be announced soon.''
The tour was set to begin in Baltimore on March 15 with more than 30 shows in the US and Canada and Mariah previously revealed that she plans to bring her five-year-old twins Moroccan and Monroe with her.
She said: ''Roc and Roe do get to come. They love to go onstage and actually they are very musical already.
''They have their school, and they have their teacher. They are doing really well but they don't love the school, let's just put it that way. But they are happy when they get to go with me on tour and there's other kids there, too, so it's good.''
Mariah, 46, also admitted that staying relevant in the music industry for over 20 years has not always been easy.
She said: ''It's very difficult, especially the way the business is now. I truly love music and always have. It's not like ... ''Oh, here's a way to get famous.'' It wasn't any of those things. It was my release, it was my everything and it still is. So I think that I'm just grateful that people still tune in.''
'Smalls Change (Meditations Upon Ageing)' arrives in April.
The two awards have made for a great 72nd birthday present for the country music icon.