KABUL (Reuters) - Donor nations are likely to pledge a total of $4 billion in civilian assistance for Afghanistan at an aid conference in Japan next month, President Hamid Karzai said on Thursday. Donor nations will gather in Tokyo to define future foreign support for reconstruction and development in desperately poor Afghanistan, which after over ten years of the NATO-led war is heavily reliant on outside aid and suffers from widespread graft. The head of Afghanistan's central bank said this week that his country would need $6-7 billion a year in aid over the next decade to help the economy grow. Karzai, speaking to parliament, also said that donor nations were expected to provide $4.1 billion a year post-2014 to finance Afghanistan's security forces.