JOHANNESBURG (AFP) - Nelson Mandela remains in a "stable but critical" condition, but "continues to respond to treatment," according to the South African government, issuing its first update on his health since September.

"The health of the former President remains much the same," according to a statement issued after President Jacob Zuma visited the anti-apartheid icon at his home Monday.

The 95-year-old was discharged on September 1 to receive intensive care at home, after nearly three months in hospital for a lung infection. The government has refused to give details about his condition, citing the need for privacy, but said "he continues to recover."

Mandela's former wife this week told a local newspaper that Mandela remains "quite ill" and is unable to speak because of tubes being used to clear his lungs of liquid.

He is using facial expressions to communicate, Mdm Winnie Madikizela-Mandela added.

The country's anti-apartheid hero is under the care of 22 doctors, and while his pneumonia has cleared, his lungs remain sensitive, she said, adding that it was "difficult for him".

"He remains very sensitive to any germs, so he has to be kept literally sterile. The bedroom there (in Houghton) is like an ICU ward," she told the Sunday Times.

"He remains quite ill, but thank God the doctors were able to pull him through from that (last) infection."

Mandela, who spent 27 years in apartheid jails before becoming South Africa's first black leader, has faced several health scares. His most recent 86-day hospital stay was his longest since he walked free from prison in 1990.