JOHANNESBURG (AP) — Southern and eastern African countries that account for more than half the continent's population and GDP are moving toward a free trade agreement that is as much about development as opening borders and dropping tariffs. At a summit Sunday, 26 governments will set timetables for allowing people and goods to move freely from Egypt down to South Africa and from Angola across to Madagascar. Leaders will also try to push forward infrastructure development and projects to support industry and manufacturing in the zone, with the hope of turning local entrepreneurs into regional powerhouses and attracting foreign investment. Challenges remain, including overcoming corruption and ensuring political stability. But experts say Africa needs to come together. The World Bank says trade among countries in sub-Saharan Africa accounts for just 10 percent of total trade, compared to 60 percent within Europe, 40 percent within North America and 30 percent within Asia. Ruth Kagia, head of World Bank operations in South Africa, said at a conference in the days before Sunday's summit that by failing to do business with one another, Africans are missing opportunities for faster growth and more jobs. Improving regional trade in Africa requires more than just dropping tariffs. Already, according to the World Bank, nearly 85 percent of trade is duty free among members of the Southern African Development Community, which is joining members of the Common Market for Eastern and Southern Africa and the East African Community in the planned free trade zone. Part of the problem is that African economies built on exporting raw mineral and agricultural materials have little to trade with one another. In addition, trade minister Rob Davies of South Africa told reporters that as a legacy of colonialism, African transport networks are designed to take goods from the heart of the continent to its coasts, which does not encourage trade between countries. "They do not connect up the different countries," said Davies, whose country is hosting Sunday's summit. Joshua Kivuva, a political scientist at the University of Nairobi, said corruption is a major impediment. Crossing Kenya — without encountering any border posts — can mean stopping at dozens of police and other roadblocks "where you have to bribe or you are delayed," Kivuva said. "I think those are the basic things which each country needs to sort out before they start talking about this grand integration mechanism," he said. He also pointed to the dominance of South Africa's economy. "The problem of the other East African countries or the upper part of east and central Africa is the fear that they will just be reduced to captive markets for South African goods," Kivuva said. The kind of violent political upheaval Egypt and Libya, both part of the zone, are currently experiencing will hobble progress as well. Slowly, members of the proposed zone are taking steps to overcome the difficulties. It's common at African border points for trucks laden with goods to wait for days in line to clear customs and conduct other formalities. In the three years since the Common Market for Eastern and Southern Africa, the East African Community and the Southern African Development Community pledged to integrate into one free trade zone, they have been able to clear red tape at just one border crossing, between Zambia and Zimbabwe. That is along what they envision as a crucial north-south trade route. The poor state of roads and rail networks also hurt, as does inadequate power supply. Officials envision the free trade zone members lobbying together for aid and investment, presenting coherent and integrated plans. To move goods duty free, multinational companies will have to open factories in the zone. Jose Fernandez, the U.S. assistant secretary of state for economic, energy and business affairs, said Washington wants to help African economies integrate, and will focus on infrastructure. Foreign investors will be drawn to the bigger markets a free trade zone can offer, Fernandez said. "African countries are going to have to take the lead in breaking down their own trade barriers," Fernandez said. For all its problems, thanks to decades of market reforms and new partnerships with burgeoning economies in Asia, Africa is growing. Africa's economy is recovering better than most regions from the global recession. The International Monetary Fund predicts sub-Saharan Africa's GDP will grow by more than 5 percent this year and next, compared to less than 3 percent for both those years for the United States. Wal-Mart, the giant U.S.-based retailer, has taken notice of the continent's growing consumer class. It is entering Africa for the first time, getting approval from regulators last month for a $2.4 billion deal to buy a controlling share of a South African chain that has stores across the continent. Integrating economies will help the continent build on its successes. Davies, South Africa's trade minister, said the three trade blocs behind the free trade agreement have a combined population of 533 million, or 57 percent of the combined population of African Union member states, and a combined GDP of $833 billion, or 58 percent of the continent's GDP. The three bloc's memberships already overlapped, making it natural for them to come together. Davies said their free trade agreement could be the beginning of a continent-wide enterprise. "The African continent is now being looked at as a source of economic opportunity," Davies said.