STORY: Pope Francis has said sorry to the people and governments of South Sudan and Democratic Republic of Congo after he was forced to cancel an African trip next month because of a problem with his knee.
Speaking during his weekly address in St Peter's Square, the pontiff said he was postponing the trip "with great regret".
"I ask you to pardon me for this", he said, adding that he wants to visit "as soon as possible."
The Vatican said the decision to cancel the July 2-7 trip was taken at the request of the Pope's doctors.
They have been treating him for a torn ligament in his knee.
The trip to South Sudan and Congo, in the summer heat, would already have been difficult for the 85-year-old even without mobility problems.
It would have entailed five plane journeys and three Masses that would have required him to remain standing for long periods.
However, the cancellation means a visit to South Sudan, repeatedly postponed because of security concerns, has once again been put off.