The United States and Nigeria, black Africa's most influential state, remained widely divided on their approaches for achieving independence for South African-administered Namibia, according to a joint communique issued after an almost two-hour meeting between U.S. Vice President George Bush and Nigerian Vice President Alex Ekwueme.

In the communique, Bush was said to have reviewed with Ekwueme efforts to remove all foreign forces from southern Africa, a clear reference to U.S. support for the removal of Angolan-based Cuban troops leading to Namibian independence. Ekwueme, on the other hand, reiterated Nigeria's position that Cuban troops in Angola must not be a condition for Namibian independence.

In response to questions after the joint statement was read, Bush and Ekwueme revealed that their two governments continue to differ on how best to bring about change in the South African government's policy of apartheid, or racial segregation.

"There are some differences that we spelled out, faced up to very frankly" on Namibia, Bush said at a short news conference.

Ekwueme said that in contrast to U.S. policy, Nigeria "believes in mandatory economic sanctions because we believe that is the shortest way to get South Africa to reassess" and change the apartheid system. "We would like American policy to change" regarding sanctions, Ekwueme continued, "but we will continue to hold a dialogue with the United States" on South African issues.

In barbed references to their disagreements, however, Ekwueme in a toast at a dinner tonight returned to the Namibian issue.

"South African intransigence is not so much concern for the presence of Angolan-based Cuban troops as a ruse to further delay the independence of Namibia and what the apartheid regime itself seems to admit, the inevitable triumph of the Southwest African Peoples Organization in any free and fair elections," said Ekwueme. "We have seen the South Africans stall before," he said to Bush, adding, "One may rightly ask: What next, Mr. Vice President?"

Ekwueme also said that from his discussions with Bush "it was evident, nonetheless, that some progress has been made on Namibia." Nigerians "trust that your administration will exert all possible pressure on South Africa to ensure that no further setbacks are encountered," he added.

In his prepared remarks, Bush said at the dinner that Namibia's independence "is one of the highest priorities of President Reagan's administration" and is a problem that "will have our total dedication and determination."

Bush will interrupt his schedule Sunday morning to fly from Lagos to Moscow to attend the funeral of Soviet President Leonid Brezhnev Monday. Bush plans to resume his African trip on Tuesday.