WASHINGTON, Dec 1 (Reuters) - U.S. climate envoy John Kerry said on Wednesday that big greenhouse gas emitting countries like China, India, Russia and others must move faster to help the world avert the worst impacts of global warming. Pledges by governments to cut carbon dioxide and methane emissions are currently insufficient to limit global warming to an international target of no more than 1.5C above pre-industrial levels this century. "And that means you have China, India, Russia, Brazil, Mexico, Indonesia, South Africa, a group of countries that are going to have to step up," Kerry said. "And we have to help them," Kerry said in an interview at the Reuters Next conference. "This is not just unloaded responsibility on them." Kerry said Washington was engaging with countries to help them accelerate a transition to cleaner forms of energy and reduce emissions. He pointed to U.S. support for India"s clean energy initiatives, as well as a joint agreement the United States secured with China last month in which Beijing committed to accelerating emissions cuts. Kerry added that private investment in clean-energy technologies - including green hydrogen, long-term battery storage, modular nuclear reactors and carbon capture - was also crucial to addressing climate change. World governments agreed last month during a climate conference in Glasgow, Scotland, to revisit their national emission-cutting pledges in 2022 to help ensure the world can meet the 1.5C target set by the Paris Agreement in 2015. Scientists have warned crossing that threshold could unleash catastrophic climate impacts from sea level rise to more frequent powerful storms, droughts and floods. To watch the Reuters Next conference please register here https://reutersevents.com/events/next/