Al Gore, the high-profile climate change campaigner and former U.S. vice president, said Japan would abdicate leadership responsibilities as a top global economy if it sustains its support for coal.

Speaking Thursday on the sidelines of an event hosted by environmentalists in Tokyo, Gore added his voice to criticism of the pro-coal policies of Japan, which was blocked from speaking at last month’s United Nations climate summit in New York.

“If they build as many new coal plants as some now propose, and subsidize as many new coal plants in other countries as they now have planned, of course that would be a massive policy failure,” Gore said.

Gore’s 2006 “An Inconvenient Truth” documentary and book galvanized the climate change movement. He shared the Nobel Peace Prize with the Intergovernmental Panel on Climate Change for raising awareness of the threat posed by global warming.

Along with China and India, Japan has been one of the biggest backers of new overseas coal-fired plants through loans and investment. The government’s development strategy abroad aims to boost infrastructure projects in key industries, including coal and gas. In Vietnam, for example, the Japan Bank for International Cooperation, Sumitomo Corp., and a number of Japanese banks have provided funds for a major new coal plant.

At home, Japan faces some of the same kinds of “abusive policy obstacles” as parts of the United States where fossil fuel-burning utilities influence regulators to put up roadblocks to renewable energy, Gore said.

The Ministry of Economy, Trade and Industry, which sets Japanese energy policy, didn’t respond to a request for comment.

Japan will add 10 gigawatts of coal-fired electricity over the next five years, with the fuel’s contribution to the total energy demand peaking at 36 percent by 2024, according to BloombergNEF. In the meantime, policymakers have put the brakes on Japan’s solar program, targeting only flat to modest growth over the next decade, according to BNEF.

Gore said he met earlier this week with a number of Japan’s corporate leaders, including representatives from banks, the powerful Keidanren (Japan Business Federation), and METI.

He also met Shinjiro Koizumi, the charismatic new environment minister and son of a former prime minister, who has said fighting climate change needs to be “sexy.” Gore said Koizumi may be able to leverage his media appeal to have a greater influence on Japan’s energy mix and climate policy.

“I’m impressed that he is a fresh voice very committed to the environment and very different in his outlook compared to most of the Abe Cabinet,” Gore said, referring to Prime Minister Shinzo Abe. “But again he is new and we’ll have to see.”

The workshop was the 43rd hosted by Gore since he founded what’s now called The Climate Reality Project in 2006. It was the organization’s first event in Tokyo. Over the course of an almost three-hour lecture, he battered the audience with a barrage of climate data and consequences. Much of it was updated within the last 24 hours and included specific risks to Japan.

Looking toward the 2020 presidential race in the U.S., Gore said he is encouraged that every Democratic candidate has made climate a top priority but said he doesn’t intend to publicly support a specific candidate. He has a tentative plan to hold all of his organization’s training events in the U.S. next year, rather than having half of them outside the country, given the importance of the topic in the race.

Gore’s presentation in Tokyo also focused on political instability, soaring economic costs, food insecurity and rising numbers of climate-related refugees as major impacts already being felt, as well as rising death tolls around the world from increased heat, storms, flooding, disease and fossil-fuel-related pollution.

“We are not yet gaining on the crisis, because it’s still getting worse faster than we are mobilizing to solve it,” he said. “But we’re gaining momentum so rapidly that we may soon be gaining on the actual problem.”