Bruce Springsteen's stomach illness "has been a monster".
The 74-year-old icon announced in September that he was postponing the remainder of his 2023 tour dates, after being diagnosed with peptic ulcer disease.
Springsteen has now admitted that it's still "rocking [his] internal world".
The award-winning star said on SiriusXM: "Let me take a moment and thank my fans affected by our postponed shows for their understanding."
"I am deeply sorry but this belly thing, despite my ability to laugh at it, has been a monster and is still unfortunately rocking my internal world."
Springsteen previously confirmed that he will continue to receive treatment for the illness for the remainder of 2023.
A statement on Instagram explained: "Bruce Springsteen has continued to recover steadily from peptic ulcer disease over the past few weeks and will continue treatment through the rest of the year on doctor's advice."
"With this in mind, and out of an abundance of caution, all remaining 2023 tour dates for Bruce Springsteen and The E Street Band will be postponed until 2024."
"Rescheduled dates for each of the 2023 shows, including those postponed earlier this month, will be announced next week, all taking place at their originally scheduled venues."
"When the new 2024 dates are announced, those unable to attend on the new date who purchased their tickets through official ticketing companies have 30 days to request a refund."
"All tickets for postponed performances will remain valid for the newly announced dates."
Springsteen also thanked his fans for their support.
He said: "Thanks to all my friends and fans for your good wishes, encouragement, and support. I'm on the mend and can't wait to see you all next year."