"If we are to succeed in Paris it will require not only political commitment, but also financing," he said in a speech to French ambassadors meeting in Paris.
The pledge to raise that amount of money annually by 2020 “was a promise that already has not been kept,” Hollande said. “It is now a requirement. Without 100 billion, there will be no deal in Paris.”
He said the sum is “indispensable” to help poorer nations cope with extreme weather and rising seas, and to develop their economies cleanly - as promised by rich governments in 2009.
Group of Seven leaders were criticised in June for their failure to outline a clear path for increasing climate aid up to 2020, from the current level of around 30 billion euros per year.
Representatives from 195 nations are expected to attend the Paris conference known as COP21, which runs from 30 November until 11 December. The participating countries have until 1 October to submit their national greenhouse gas emission commitments. Only 55 countries have submitted their declarations so far.
"We are moving forward, but the most difficult is yet to come, so we have to move quickly," Hollande added, announcing that he would travel to Beijing in early November to work with Chinese President Xi Jinping, and then to Seoul, the seat of the Green Climate Fund.
The conference is seen as one of the last chances of a global agreement on the fight against climate change. France hopes to lead to the conclusion of a universal and binding agreement to keep global warming below 2 ° C.