TOKYO, May 17 (Reuters) - Rich nations should boost financial and technical support to poorer countries to help them tackle climate change and achieve similar decarbonisation goals, a senior Japanese environment ministry official said ahead of a G7 summit in Hiroshima. Developed countries promised in 2009 to transfer $100 billion annually between 2020 and 2025 to vulnerable states hit by increasingly severe climate-linked impacts and disasters - but that target was never met. G7 energy and climate ministers discussed how to meet that goal when they met in the Japanese city of Sapporo last month. "All countries should follow the good example of Japan so that we could achieve the $100 billion goal," he said, adding that he hoped that the level would be achieved as soon as possible and maintained through 2025. Developing countries say they need far more support than that from the rich nations, who are responsible for most of the greenhouse gas emissions, otherwise they cannot afford to cut CO2 emissions.

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