Archbishop Desmond Tutu is being treated for an infection in a Cape Town hospital.
In a statement released by his charitable organisation, the Desmond and Leah Tutu Legacy Foundation, his daughter the Reverend Canon Mpho Tutu said she hopes he will be home again soon.
No details were given on the nature of the 82-year-old's infection, but it was described as "persistent".
His admitting to hospital comes just a few days after he renewed his wedding vows to his wife, Nomalizo Leah, to mark their 60th wedding anniversary.
The retired Anglican bishop is an icon in his home country of South Africa and across the world due to his fight against apartheid, for which he won the Nobel Peace Prize in 1984.
Tutu has lived with prostate cancer for 15 years, and has had a number of other health problems in the last few years.
He had a minor elective surgery in 2011, and was back in hospital fighting another infection two years later.
He has cancelled plans to travel to Rome in December, so he can continue fighting his prostate cancer.
He retired from public life in 2011, but continues to travel and make public appearances, although far less than he did before his retirement.Reuse content