Former president S R Nathan remains critically ill and unconscious, said Prime Minister Lee Hsien Loong yesterday.

Mr Nathan had a stroke on July 31 and is being treated at the Singapore General Hospital.

He is restful and well cared for by doctors and nurses, said Mr Lee, who visited Mr Nathan on Friday and gave an update on his condition before starting his National Day Rally speech.

"His family has been touched by many of your good wishes," Mr Lee said.

Singapore's sixth and longest-serving president, Mr Nathan, was head of state from 1999 to 2011.

During Mr Lee's Mandarin speech last night, he praised Mr Nathan as a "shining example" of a head of state who united all Singaporeans.

As president, he looked after the interests of all Singaporeans, proactively reached out to all races and got to know them well, Mr Lee said.

Royston Sim