LONDON (Reuters) - British billionaire Chris Hohn is aiming to force hundreds of U.S. and European companies to slash their greenhouse gas emissions by enlisting global investors to demand an annual vote on their climate plans at shareholder meetings. Hohn, who has emerged as a major investor voice on climate change, set a precedent last month by using a shareholder resolution to force Spanish airports operator Aena AENA.MC to draft a new climate plan and submit it to an annual vote. Hohn, founder of the TCI hedge fund, aims to replicate that model at many more companies in the next two years by mobilising investors to sponsor similar resolutions as part of his new Say on Climate www.sayonclimate.org campaign. “Of course, not all companies will support the Say On Climate. There will be fights, but we can win the votes,” Hohn told a webinar with representatives of pension funds and insurance companies on Thursday. Hohn"s Children"s Investment Fund Foundation said the funds taking part represented more than $3 trillion in assets. The webinar was later posted here on the Say on Climate website. Hohn’s campaign opens a new front in a wider push by activist investors on climate change. Under Hohn’s plan, shareholders submit a resolution requesting companies to disclose their greenhouse gas emissions, present a plan to reduce them, and give shareholders an annual nonbinding advisory vote on that plan. Rather than push for specific action by groups of high-emitting companies, such as oil and gas majors, Hohn aims to drive a systemic shift so that it becomes standard practice for all major companies to submit climate plans for annual scrutiny. “We think we need an annual general meeting shareholder vote to create an accountability mechanism for the execution of the plan – otherwise companies will do as little as they can get away with,” Hohn said. Earlier this month, U.N. climate envoy Mark Carney backed the idea.