U.S. President Donald Trump announced plans to invest $700 million of federal funds in order to revive the U.S. coal industry, citing a Cold War-era law that grants the president broad authority to support industries considered vital to national security.

"So today we're taking historic action to bring down the price of energy and the cost of living for all Americans with the power of clean, beautiful coal," Trump said at the White House on June 4.

According to BBC News, the investment, under the Defense Production Act, comes in an effort to insulate Americans from rising energy costs, including gas at more than $4 per gallon, because of the war with Iran.

"As a result of the $700m investment that I'm announcing today, we will protect 14 coal plants and 42 coalmines, a tremendous number, and build two new coal plants and one massive new export terminal," Trump said.

The funding will be split between $500m going towards saving 14 existing coal plants and opening a new export terminal in California, plus another $200 million, granted by the Department of Energy, to build new coal plants in Alaska and West Virginia, the first new plants in the U.S. since 2013.

Trump said that the construction of a coal export terminal in Oakland, California will create more than 1,400 jobs, with the total package supporting around 14,000.

The coal plants targeted are in Kentucky, North Carolina, Indiana, Tennessee, Arkansas, Arizona, Oklahoma, North Dakota, Wisconsin and West Virginia.

BBC News said the president argued that successful countries rely on coal, before criticizing what he called "failure countries" for investing in renewable energy sources such as wind power.