But even as Zuma was suggesting that Mandela's health was improving, one of Mandela's daughters suggested otherwise. "I won't lie. It doesn't look good," Makaziwe Mandela told the South African Broadcasting Corporation. "Anything is imminent."
Mandela, she said, was still giving the family a sense of hope because he was reacting to touches and opening his eyes, and that "we will live with that hope until the final end comes."
She and Zuma also took aim at the foreign media, accusing them of spreading rumors and publishing unconfirmed reports about Mandela's condition. Zuma appealed "for respect for the privacy and dignity of the former president."
Hundreds of journalists have arrived in South Africa, waiting outside Mandela's hospital, as well as his home in Houghton, an upscale Johannesburg neighborhood, and in Qunu, his ancestral village.
Makaziwe Mandela described the media as "vultures waiting when a lion has devoured a buffalo, waiting there for the last carcasses. That's the image that we have, as a family."
In Dakar, Obama used his personal reflections of Mandela to help push democratic values at a time when sub-Saharan Africa has emerged as one of the fastest-developing regions in the world, and other countries, including China, have begun ramping up their own investments on the continent.
The president acknowledged the United States has been neglectful, but he pledged to support countries such as Senegal, which Obama held up as an example to neighboring countries for its pursuit of a free society whose government is held accountable.
In a meeting with Senegal President Macky Sall, Obama praised him for pursuing a case against former Chad dictator Hissene Habre, whose administration is accused of killing thousands, for crimes against humanity. And the president pledged to support Senegal's trial of Habre with resources, including a $1 million grant to the special court, administration officials said.
But the challenges that remain were apparent during a joint news conference when Obama hailed the U.S. Supreme Court's ruling this week that a law denying federal benefits to married same-sex couples is unconstitutional. Sall, asked by a reporter whether he would pursue changes to Senegal's law that criminalizes homosexuality, said he did not think his country was ready for such a change.
"These issues are societal," he said. "We should not have one standard model that's applicable to all nations."