Prime Minister Yasuo Fukuda is expected to announce a plan for Japan to offer $10 billion over the next five years to help African nations tackle climate change in his speech at the opening ceremony of the Tokyo International Conference on African Development in late May, government sources said Sunday. Japan has been studying the feasibility of doubling official development assistance to Africa over the next five years as well as doubling trade and investment, they said. Japan is hoping to demonstrate its readiness to exercise leadership in the fields of climate change and African aid, which will top the agenda at the Group of Eight summit in Hokkaido in July, they said. Fukuda will advocate the launch of the new lending system and the beefing up of trade insurance in order to reduce risk and promote Japanese investment in Africa.