President Trump said Tuesday that Japan and South Korea have expressed interest in partnering with the United States on a $44 billion plan to produce and export natural gas from Alaska, reviving interest in one of the world’s biggest energy projects.

The project, known as Alaska L.N.G., involves constructing an 800-mile pipeline from fields north of the Arctic Circle to southern Alaska, where the natural gas would be liquefied and shipped to Asia. China and Japan are the world’s two biggest importers of liquefied natural gas.

Because of its high costs and the time required for construction, Alaska L.N.G. has been viewed as a long shot within the industry. For years, major energy companies and officials in Japan and South Korea rebuffed requests from Alaskan delegations to participate, stalling the project’s decades-long progress.

However, under the threat of tariffs from Mr. Trump, officials and executives in Japan, South Korea, and Taiwan have started exploring ways to invest in Alaska L.N.G. The discussions have included financing for the project’s infrastructure and signing long-term contracts to purchase its gas.

“Japan and South Korea and other nations want to be our partner with investments of trillions of dollars each,” Mr. Trump said on Tuesday during his address to Congress. “It’s all set to go,” he said of the project, which would be one of the largest energy investments in U.S. history.

Mr. Trump promised to boost the production of fossil fuels during his campaign by speeding up the approval of permits and opening up new areas for exploration. Any additional output would push U.S. production beyond already record-high levels. The United States is also the world’s biggest exporter of natural gas.

Mr. Trump did not explain how the project could see trillions of dollars in investment. But the serious consideration in Alaska L.N.G. shows how, just over a month into his presidency, Mr. Trump is already beginning to make potentially lasting marks on the U.S. energy industry.

In his speech, Mr. Trump reiterated his stance on slowing the U.S. transition to renewable energy while revitalizing fossil fuels despite concerns over climate change. “We have more liquid gold under our feet than any nation on earth,” he said. “It’s called drill, baby, drill.”

Venezuela is believed to have the world’s largest oil reserves.

A spokesman from Japan’s government did not immediately respond to requests for comment.

Jin Yu Young contributed reporting.