SHARM EL-SHEIKH, Egypt (AP) — The leader of the small island nation of Tuvalu has proposed a treaty against fossil fuels as world leaders make the case for tougher action to tackle global warming. Tuvalu Prime Minister Kausea Natano said the world should confront climate change the way it does nuclear weapons, by agreeing to a non-proliferation treaty that stops further production of fossil fuels. The proposal came as vulnerable nations pushed for more action and money at international climate talks in Egypt. But big polluters remained divided over who should pay for the damage industrial greenhouse gas emissions have done to the planet.