NEWS ANALYSIS : Compromise, Positive Atmosphere Called Essential for S. Africa Accord : Voting rights: But some experts say De Klerk’s power-sharing arrangement is impractical.

President Frederik W. de Klerk’s controversial proposal for a constitution giving blacks a vote but preventing a black majority from running the country suggests that future power-sharing talks with Nelson Mandela’s African National Congress will be difficult and contentious.

But constitutional analysts said Thursday that De Klerk and Mandela’s opposing plans for a future South African government have important similarities as well and that both sides will need to overcome their distrust and make compromises.

“Obviously, they are fighting for their own negotiating advantage and are emphasizing the differences,” said Barry de Villiers, head of the Center for Constitutional Analysis at the Human Sciences Research Council in Pretoria. “But there’s a lot of common ground here.”

De Villiers and other analysts predict that the final shape of South Africa’s constitution will be determined less by the details of each side’s proposals and more by the atmosphere prevailing when all parties sit down at the bargaining table.

“If there’s a euphoria, a feeling of ‘Let’s reach out to one another,’ then I think everyone will support the final product,” De Villiers said.

De Klerk’s constitutional plan, unveiled Wednesday, was approved unanimously by a special federal congress of the ruling National Party and has been welcomed by liberal and moderate whites, including the business community. But, on the political left, it has been sharply criticized by the ANC and the Pan-Africanist Congress as a thinly veiled attempt to maintain white privileges entrenched during four decades of apartheid.

De Klerk’s white, right-wing opponents have denounced the document for the opposite reason, saying that it would result in black domination and white oppression. The Conservative Party also called the provisions for weak central government “a recipe for revolution.”

Meanwhile, the legislative assembly of Kwazulu, the homeland run by Inkatha Freedom Party leader Mangosuthu Gatsha Buthelezi, also gave De Klerk a thumbs-down.

“We cannot approve of the . . . proposals in their present form,” Buthelezi’s assembly said. But it gave no specifics and said it would discuss its objections with De Klerk’s ruling National Party.

The constitutional proposals that De Klerk’s party and the ANC will bring to negotiations both envision a three-tier government, with federal, regional and local government authorities. And the two sides agree on the need for an independent judiciary, a bill of rights, universal voting rights, some protection for minority parties and no specific references in the constitution to race.

Their major points of disagreement surround the office of president, the presidential Cabinet, the composition and powers of a two-chamber parliament and the powers of regional governments.

De Klerk has proposed a three-member presidency made up of the leaders of the three parties gathering the most votes in a nationwide election. All decisions would be made by consensus, meaning each leader would have veto power.

That is an impractical arrangement that would paralyze effective government, constitutional experts say. If an election were held today, for example, that presidency might be made up of Mandela, De Klerk and Andries Treurnicht, leader of the pro-apartheid Conservative Party. Those three men rarely agree on anything.

The collective presidency has been used in Yugoslavia with poor results, and in Switzerland, where it has been successful but is part of a political agreement and not constitutionally entrenched.

Both De Klerk and Mandela have proposed a two-chamber parliament, with one house elected in a one-person, one-vote election, and the second house, like the U.S. Senate, giving equal representation to geographic regions.

But they differ in two important respects. The ANC would give the Senate the power only to delay and reconsider legislation, while De Klerk’s plan would require both chambers to agree on all laws.

And the ANC would allocate seats in the Senate according to a party’s proportion of the vote in the region. De Klerk would give all significant parties in a region equal numbers of seats in that body--regardless of their actual support.

The effect of De Klerk’s proposal would be to give minority political parties, most of which are still drawn along racial lines in South Africa, a veto in the government process. That would make tasks such as the adoption of a federal budget difficult if not impossible.

Most analysts believe De Klerk will be forced to give up his proposal for a collective presidency, as well as the unrepresentative second parliamentary chamber, at the bargaining table. But they say the ANC may have to compromise on the makeup of the presidential Cabinet and the powers of regional governments.

The ANC wants a Cabinet appointed by the president from his own party. But De Klerk worries that such an arrangement, as has been used by successive National Party governments for 40 years, concentrates too much power in the hands of one party. The president prefers there be a multi-party Cabinet.

And while the ANC favors a strong central government, with minimal powers for regional governments, De Klerk wants strong local and regional governments with a weak central government. The president also has suggested a qualified franchise at the local level, where the votes of property owners, renters and taxpayers would be worth more than those of other residents, such as squatters or domestic workers.

Some experts are concerned that De Klerk’s constitution, with its many built-in protections for minorities, would solidify the deep divisions in society rather than overcome them.