Sirt, Libya, July 03 (QNA) - African Union (AU) members have agreed a plan to give its executive arm enhanced powers to co-ordinate common-interest policies, officials say. But the African Authority will not be able to act internationally unless it has a mandate from heads of state, the AU members agreed during a closed session in the Libyan town of Sirte. Meanwhile, the plan had been resisted by South Africa and Nigeria, among others, who objected to giving the authority too much power. The new African Authority aims to simplify the AU''s structure, allowing more control over diplomatic, trade and defense matters. Libyan leader Muammar Gaddafi, also the current AU chairman, had pushed hard for the grouping to be given wider regional and defense powers, but faced opposition from the continent''s largest economy, South Africa, and oil-producing nations like Angola and Nigeria, who expressed concerns about losing sovereignty over their own defense and foreign policy issues. The changes to the AU have yet to be ratified by member states, who have also agreed to discuss the financing of the plan at a later date. (QNA)