President Kgalema Motlanthe �I am deeply humbled and honored by the faith and confidence that the members of this assembly have in me.�

South Africa’s Parliament, which elects the president from among its members and is dominated by the African National Congress, elected Kgalema Motlanthe with 269 votes to 50 for the main opposition party’s nominee.

Jacob Zuma, whose allies engineered Mr. Mbeki’s ouster, watched from the public gallery. Mr. Zuma was not eligible for the presidency because he is not a member of parliament.

President Motlanthe is expected to step aside after elections next year, when Mr. Zuma is expected to become president.

When the vote results were announced, members of Parliament rose to cheer, and President Motlanthe gave a two-thumbs up salute to the gallery. He was sworn in shortly afterward at the presidential office in the Parliament complex.

Later he briefly addressed the house in measured tones that reflected his reputation as a cool, no-nonsense politician.

“I am deeply humbled and honored by the faith and confidence that the members of this assembly have in me,” he said. President Motlanthe stood, rocking slightly, as he recited the oath of office, pledging to “do justice to all.”

The festive mood at the parliament session and swearing-in ceremony was in marked contrast to a tumultuous week in South African politics. ANC lawmakers sang anti-apartheid anthems and cheered when President Motlanthe cast his vote.

Mr. Mbeki did not attend the National Assembly session and Cabinet ministers who have said they were leaving with him also were absent. Among them were the former deputy president, defense minister, intelligence and prisons ministers.

Other members of Mr. Mbeki’s team have said they would be willing to serve in the next administration.

On Sept. 20, the ANC ordered Mr. Mbeki to quit. Urged on by Mr. Zuma’s leftist allies, it acted after a judge threw out a corruption case against Mr. Zuma on technical grounds and said Mr. Zuma may have been a victim of Mr. Mbeki’s political machinations.

The ANC struggled to reassure South Africa and the world there was no reason to fear instability in Africa’s economic and diplomatic powerhouse.

But the situation is fragile, as was clear Sept. 23 when Mr. Mbeki’s office announced that 13 ministers and three deputies had resigned from the 28-member Cabinet, among them the highly respected finance minister, Trevor Manuel.

South Africa’s stocks and currency reeled. Only later did it become clear that six of those who resigned, including Mr. Manuel, had already told the ANC they were willing to serve in a new government. Mr. Manuel was expected to be named to a new Cabinet.

Mr. Zuma is seen as owing his rise to support from labor, the South African Communist Party, and the ANC’s increasingly impatient youth wing. But Mr. Zuma has said repeatedly he does not plan a major departure from the free market policies of Mr. Mbeki and Mr. Manuel. South Africa enjoyed unprecedented growth during Mr. Mbeki’s nine-year tenure, but critics say he did too little to ensure the new wealth trickled down to the Black majority.

For all the uncertainty of recent days, some South Africans say the smooth transition was a mark of the maturity of their democracy 14 years after the end of apartheid.

Associated Press Writer Michelle Faul contributed to this report.