Meanwhile, members of Mandela's family gathered at his home village of Qunu in the country's Eastern Cape province, local news reports said. Few details were provided except that a meeting had been called to discuss "delicate" family matters.
Other relatives were seen visiting the hospital where Mandela is receiving treatment, as they have done on previous days.
Mandela, who became
"Doctors continue to do their best to ensure his recovery, well-being and comfort," the government statement said.
It is a day when South Africans are encouraged to devote 67 minutes to acts of kindness in honor of the 67 years that Mandela worked for equality in the country, from 1942 until his retirement from public life in 2009.
"We must support him and support his family," Zuma said in the statement. "We must demonstrate our love and appreciation for his leadership during the struggle for liberation and in our first few years of freedom and democracy by living out his legacy and promoting unity, non-racialism, non-sexism and prosperity in our country."
Staff writer Robyn Dixon contributed to this report from Johannesburg, South Africa.