African Union chairperson and Ethiopian Prime Minister Hailemariam Desalegn.
African Union (AU) chairperson and Ethiopia's Prime Minister Hailemariam Desalegn told leaders as he opened the celebrations they should seek to "create a continent free from poverty and conflict, and an Africa whose citizens enjoy a middle income status".
Today's 54-member AU is the successor of the Organisation of African Unity (OAU), established amid the heady days as independence from colonial rule swept the continent in 1963.
"While our founders met for the formation of the OAU at the dawn of the independence period 50 years ago, it is fitting that we are meeting here today at a time when Africa is rising," Hailemariam added, speaking in the modern Chinese-built AU headquarters.
Leaders said the celebrations would boost the movement to support pan-Africanism.
"When we therefore talk about African solutions to African problems, it is because we know that we can only permanently silence the guns if we act in solidarity and unity," said AU Commission chief Nkosazana Dlamini-Zuma.
But while speaking optimistically about "the bright future of Africa", she also noted that "the self-reliance and economic independence that our founders spoke of remains a bit elusive and social inequalities remain".
Economic emancipation
President Jacob Zuma said on Saturday that Africa Day marks the quest for unity and the political and economic emancipation of the continent's people
"As we mark the 50th anniversary of the OAU, we must intensify our efforts and our calls for the reform of the governing global order," he said in a statement.
He said the OAU provided a sense of purpose for the African people to restore their freedom, dignity and to strive for a better life for all Africans.
"While we rightfully celebrate the 50th anniversary, we are cognisant of the challenges we face," Zuma said.
"The road ahead to attain peace, stability and prosperity on the African continent for all her peoples is still arduous."
He called on all leaders of the continent to sharpen their resolve and through the AU, raise their collective voices and confront current problems.
Festivities
African leaders were joined by UN leader Ban Ki-moon, Brazil's President Dilma Rousseff and US Secretary of State John Kerry, while France's President Francois Hollande and China's Vice-Premier Wang Yang were expected to attend celebrations later.
But Hailemariam singled out Beijing, expressing his "deepest appreciation to China for investing billions … to assist our infrastructure endeavours".
Saturday's celebrations will be followed by a two-day AU summit meeting, to tackle the range of crises the continent faces.
Mass dancing troupes are set to perform musical dramas later on Saturday to some 10 000 guests in a giant hall in the Ethiopian capital, choreographed by the same team who organised the lavish opening and closing ceremonies of the 2010 World Cup and this year's Africa Cup of Nations.
The AU has budgeted $1.27-million for Saturday's celebrations, according to official documents seen by South Africa's Institute for Security Studies.
AU Commission deputy chief Erastus Mwencha said he did not have the exact figure but that some $3-million would be spent on Saturday's festivities and on other events over the coming year.
Musicians playing later include Congolese music legend Papa Wemba, Mali's Salif Keita and British-based reggae band Steel Pulse, with giant screens set up across Addis Ababa also showing the festival.
Africa's development indicators
Development indicators on the continent – including health, education, infant mortality, economic growth and democracy – have improved steadily in the past 50 years.
Africa is home to some of the fastest growing economies in the world according to the International Monetary Fund, and has attracted huge amounts of foreign investment in recent years, with Kerry praising the "economic possibilities, growth and development" on the continent.
At the same time 24 out of the 25 nations at the bottom of UN human development index are in Africa.
The AU took over in 2002, switching its name in a bid to shrug off the OAU's troubled policy of non-interference in member states' affairs, which allowed leaders to shirk democratic elections and abuse human rights without criticism from their neighbours.
In recent years, the AU's role in combat – such as its mission in Somalia to battle al-Qaeda linked Islamists – has shown it can take concrete action, even if the funding for that mission comes mainly from Western backers.
But at the same time, the splits revealed by the 2011 conflict in Libya – when members squabbled between those wanting to recognise rebels and those backing Moammar Gadhafi – showed its disunity and lack of global clout.
Gadhafi's death also stripped the AU of a major source of funding. Leaders will discuss finding backers for the cash-strapped body at the summit meeting opening on Sunday. Mali is expected to be discussed: it is preparing to receive a UN peacekeeping force to support French soldiers fighting Islamist rebels in the north since January.
The agenda will also likely include Madagascar – in political deadlock since a 2009 coup – and the eastern Democratic Republic of Congo, where UN-backed government soldiers are struggling to quash rebels. – AFP; Sapa