SINGAPORE, Oct 27 (Reuters) - The International Energy Agency (IEA) and International Renewable Energy Agency (IRENA) on Wednesday called for a massive scale-up in clean energy projects and policies at the upcoming U.N. COP26 climate summit as a buffer against volatile prices. The call from world"s top energy agencies come after the United Nations warned this week that updated pledges to reduce emissions fell short and COP26 could be the last chance to curb global warming. read more "We are sitting in a very narrow window ... So, this is really the decade, where you want to see a strong foundation of actions being focused upon, so that we are actually on track to reach net zero by the mid-century," Gauri Singh, IRENA"s deputy director-general told Reuters. Mary Warlick, IEA"s deputy executive director, reiterated the agency"s call to triple investments in clean energy by 2030 to curb climate change."We need to massively scale up clean energy investment as the longer today"s mismatch and energy investment persists, the greater the risk of future price volatility and delayed climate action," Warlick told the Singapore International Energy Week (SIEW) conference. "We look forward to an unmistakable signal coming from governments at COP26 in Glasgow," she said, referring to the global climate summit that starts on Oct. 31. Hitting the Paris Agreement goal of net-zero carbon emissions will require investments in a green transition worth 2%-3% of world output each year until 2050, far less than the economic cost of inaction, according to a Reuters poll of climate economists. read more "The pace -- at which renewables were expanding in countries -- has now got to increase. And for that, you don"t need an incremental change in policies, you need a step change," IRENA"s Singh said in an interview on the conference sidelines. "Unfortunately, you still don"t have the right policies in place in many of the countries, which I think is very critical."