The irony was that in recent weeks they seemed to be losing ground in their drive toward a peaceful settlement. Important factions, including hard-line white Afrikaners and Zulu nationalists, walked out of the constitutional negotiations that are supposed to prepare for the country’s first one person, one vote elections next April. De Klerk said early last week that if the negotiations didn’t get back on track quickly, he might have to hold a referendum seeking multiracial support for the peace process. That could mean postponing the election, and the ANC opposes any such delay.

Under the circumstances, even some supporters of the two men thought the peace prize was a bit premature. De Klerk has eliminated many aspects of apartheid since becoming South Africa’s president in 1989. But political violence, especially among rival factions in the black townships, has killed more than 11,000 people in the past three years. Mandela admits that ANC members have been involved in some of the killings, typically during turf battles against the Zulus, but he blames de Klerk’s security forces for allowing the slaughter to continue. De Klerk’s supporters say Mandela hasn’t done enough himself to stop the black-on-black killing.

When de Klerk released Mandela, ending his 27 years as a political prisoner, the ANC leader praised the white president as “a man of integrity.” Now the atmosphere between them is noticeably cooler. At a press conference after the award was announced, Mandela declined to repeat his assessment of de Klerk’s integrity. When reporters asked him what de Klerkhad done to deserve his share of the $825,000 prize, he replied frostily: “Just ask the Nobel Peace Prize Committee.”

Each man wants to appease hard-liners on his own side of the racial divide, which accounts for some of the harsh rhetoric. But personal relations between them remain stiffly formal. They sometimes have tea together during their private meetings in de Klerk’s office; they’ll even share a whisky if business runs into the evening. But de Klerk admitted last week: “We’re not personal friends.” Mandela said, in effect, that he didn’t need de Klerk’s friendship. “The reality,” said the ANC leader, “is that he and I have been placed in the South Africa of today, and we have no alternative but to work together in order to bring about a democratic South Africa.” That makes them both allies and rivals. If they achieve their common goal, Mandela will probably succeed de Klerk as president. But de Klerk hasn’t given up on his own political future; he still wants his National Party to play a strong role.

Both Mandela and de Klerk may be past their political prime. In “Chained Together,” a double portrait to be published later this month by Times Books, American journalist David Ottaway writes that Mandela’s health and physical stamina are fading, leaving him with little more than a “lofty status” as a “distinguished elder statesman.” He says de Klerk is in danger of becoming a South African Gorbachev–“an indecisive leader who was overwhelmed, and finally swept aside, by the very avalanche of changes his well-intentioned reforms had set rolling.” Ottaway argues that, despite their waning powers, the two men are still essential to each other–and to the transition away from apartheid. “They were indeed like two escaping convicts chained together and hating each other but realizing full well that they needed one another to make good their run to freedom,” he writes. But he maintains that younger leaders–notably Cyril Ramaphosa and Roelf Meyer, the chief ANC and government negotiators–have already taken over “the burden of building bridges.”

The Nobel Prize may contribute to that effort; it often seems intended to endorse a process that is not complete. “I hope that it will work to weld us together as a people,” said Archbishop Desmond Tutu, the 1984 winner. But winning the prize is not necessarily synonymous with securing the peace. In 1973, Henry Kissinger and North Vietnam’s Le Duc Tho shared the award for negotiating an end to the Vietnam War (Kissinger banked his share of the prize; Le Duc Tho declined his half). U.S. forces withdrew, and after a barely decent interval of two years, Hanoi resumed the war, gobbling up South Vietnam. After Anwar Sadat and Menachem Begin won a joint award in 1978, 15 years went by before another giant step was taken toward peace in the Middle East. By then, both men were dead, Sadat having been murdered for his peacemaking. Mandela and de Klerk have a chance to achieve their common goal much more quickly and decisively. But as things stand now in South Africa, the prize rewards good intentions, rather than lasting results.