Africa is losing out on billions of dollars in potential earnings every year because of high trade barriers on the continent, the World Bank said Tuesday."It is easier for Africa to trade with the rest of the world than with itself,” the World Bank said in releasing a new report that examines the barriers that stifle cross-border trade within Africa.The report comes on the heels of an African Union summit in Ethiopia at which leaders called for a continental free-trade area by 2017.The World Bank stressed it was even more urgent that Africa improve trade flows because of the sharp economic slowdown under way in the eurozone, an important trade partner under pressure from the bloc’s debt crisis.The World Bank estimates the eurozone slump could shave Africa’s growth by up to 1.3 percentage points this year."While uncertainty surrounds the global economy and stagnation is likely to continue in traditional markets in Europe and North America, enormous opportunities for cross-border trade within Africa in food products, basic manufactures and services remain unexploited,” said the Washington-based lender.Poor infrastructureThe report argues that the situation deprives the continent of new sources of economic growth, new jobs, and an opportunity to make important strides in reducing poverty."Trade and non-trade barriers remain significant and fall most heavily and disproportionately on poor traders, most of whom are women,” Obiageli Ezekwesili, the Bank’s vice president for Africa, said in a statement.