Conspicuous by his absence was former president, Nelson Mandela, who unexpectedly skipped the launch as his party declared its readiness to spend $15 billion to fight poverty and create new jobs.
Senior ANC officials said they had only learned of Mandela's absence belatedly, and that they had not been given a reason.
"Perhaps the only reason is that he doesn't always attend all functions," said Jeff Radebe, chairman of the ANC committee that drafted the party's 2004 election manifesto.
Neither Mandela's spokeswoman nor officials from the Nelson Mandela Foundation could be reached for comment.
Radebe said he was not sure if Mandela, who is 85 and the top draw at any ANC event he attends, was in the country.
Mandela's last major public appearance was at his annual Christmas Day party for children in his home village of Qunu.
That event followed vigorous denials by Mandela aides of reports he was planning a foreign trip for medical checks.
Mandela led the ANC to electoral triumph in the 1994 election that marked the end of white minority rule in South Africa.
No reason was given for Mandela's
absence at the rally
Thousands of supporters of the ANC thronged the 30,000-capacity Harry Gwala stadium in Pietermaritzburg, some 70 km northwest of the eastern port city of Durban, to hear President Thabo Mbeki announce the party's election manifesto.
The ruling party is expected to call elections in March or April, coinciding with the 10th anniversary of the end of apartheid.
"The ANC speaks with confidence because it has been at the head of a national effort to change our country for the better," said the party manifesto, released in Durban on Saturday. "We know that with you we can do more, better."
The manifesto, amongst others:
- Calls for closer coordination between the party and key role players in the economy to create more jobs and help in the redistribution of wealth.
- Commits to spending more than $15 billion on improving roads, rail and air transport as well as telecommunications and energy.
- Vows to ensure low interest and inflation rates.
- Promises to halve unemployment and poverty by 2014 through new jobs, skills development, a comprehensive welfare system, land reforms and improved household and community assets.
- Aims at creating one million jobs over the next five years through an expanded public works programme.
- Targets the completion of the land redistribution programme and speeding up land reform.
- Speaks of improved health services and vows to promote awareness on HIV/AIDS and provide comprehensive care, management and treatment to battle the pandemic, but does not give any figures or targets.
The choice of the capital of coastal Kwazulu-Natal province, the Zulu heartland and base of the ANC's main rival, the Zulu-based Inkatha Freedom Party (IFP), for Sunday's rally was deliberate.
The national vote is almost certain to maintain the ANC's comfortable two-thirds majority in parliament, and officials say the party's main focus will be on winning KwaZulu-Natal, the only province it does not control and the site of political violence that killed thousands in the early 1990s.
South Africans, including infants, dying
of AIDS is key target area in manifesto
Tony Leon, the leader of the opposition Democratic Alliance, meanwhile, charged that "over the past 10 years, the ANC has proved that it is very good at making promises and very bad at delivering on them".
He claimed that since 1994 one million jobs had been lost; seven million people were infected with HIV/AIDS and millions of people had become victims of violent crime, the SAPA news agency reported.