"I'm so sorry to disappoint all of you once again," Dion wrote in a May 26 Instagram message. "I'm working really hard to build back my strength, but touring can be very difficult even when you're 100%. It's not fair to you to keep postponing the shows, and even though it breaks my heart, it's best that we cancel everything now until I'm really ready to be back on stage again."
"I want you all to know, I'm not giving up," she added, "and I can't wait to see you again!"
The 55-year-old's announcement comes five months after she shared her stiff-person syndrome diagnosis, a condition that can cause muscle spasms.
"I've been dealing with problems with my health for a long time," she told fans in a December Instagram video, "and it's been really difficult for me to face these challenges and to talk about everything that I've been going through."