Cape Town - FW de Klerk was hospitalised on Friday at the Panorama Hospital, the FW de Klerk Foundation said in a statement.
The 82-year-old former president "is being treated for a condition known as pneumothorax which is an abnormal collection of air in the pleural space between the lung and the chest wall.
"He underwent a successful procedure this (Saturday) morning and it is expected that he will be discharged from hospital some time next week, " the foundation said.
De Klerk, as the leader of the now defunct National Party, served as president of South Africa from 1989 to 1994.
He shared the Nobel Peace Prize in 1993 with Struggle icon Nelson Mandela for their work in ending apartheid.
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