Thousands have been gathering since early morning for the ceremony

South Africa is preparing to swear in Jacob Zuma, leader of the African National Congress, as president.

Nearly 30 heads of state are joining an expected crowd of 30,000 at the Union Buildings in Pretoria for the ceremony.

Security is tight with streets around the Union Buildings - the president's office - closed to traffic.

Analysts say Mr Zuma, 67, brings a populist touch to the presidency, ensuring a very different leadership to that of Thabo Mbeki.

Mr Zuma was officially elected president by members of parliament on Wednesday, after the ANC won the general election two weeks ago.

He is due unveil his new cabinet on Sunday.

Torrential rain

The crowds began gathering at the Union Buildings in South Africa's capital before dawn, some singing songs in praise of their new president.

Many spoke of their excitement at being able to witness Jacob Zuma become president.

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"We are rejoicing. He's the people's leader," Nkompela Xolile told the BBC. "He knows the poor of this country."

Even a torrential downpour did not dampen spirits - in Zulu tradition, rain during an important event is a good sign.

Former South African President Nelson Mandela is also expected to be among the 5,000 invited guests - including 29 heads of state and government.

Among them are Zimbabwean President Robert Mugabe and Libyan leader Muammar Gaddafi.

As the leaders filed into the venue, musicians and traditional dancers performed on stage for the thousands of supporters who had gathered under umbrellas on the lawns below.

The inauguration will be followed by a huge concert and several more concerts and parties planned throughout the day and evening.

Epic journey

Jacob Zuma's journey to the Union Buildings has been an epic struggle, the BBC's South Africa correspondent Peter Biles says.

He was sacked as vice-president by Thabo Mbeki four years ago after being implicated in a corruption scandal - allegations Mr Zuma always denied.

The case was eventually thrown out amid evidence of government meddling in the investigation.

There is a torrential downpour. In front of the Union Buildings, there is a sea of black umbrellas sheltering all the officials who have come. Some of the crowd have sought shelter under trees and their umbrellas. Others continued to dance and sing in the rain. There is a Zulu saying when it rains before a big event: "The ancestors have given their blessing". People have been making their way to the venue since before dawn, singing songs praising Mr Zuma in the dark.

In February 2006, the controversial polygamist was acquitted of rape in a separate case, though he was widely criticised for his comments about sex and HIV/Aids.

At the time, few observers believed Mr Zuma could remain a serious contender for president, our correspondent says.

But he fought to clear his name, retained enormous popularity, especially among his fellow Zulus, and led the ANC to a convincing election victory on a pro-poor populist ticket.

Mr Zuma has listed his five priorities as land redistribution, education, health, lowering crime levels and finding decent work for all South Africans.

He has promised a more hands-on approach and to work more closely with the opposition.

"We must move quickly to implement the framework agreed by the government, business and labour to protect jobs and boost the economy," he said on Wednesday.

Source: BBC