President Joe Biden on Monday invoked the Defense Production Act to spur U.S. solar panel manufacturing and exempted tariffs on solar panels from four Southeast Asian nations for two years as part of his push for clean energy, the White House said.

The tariff waiver applies to panels from Cambodia, Malaysia, Thailand and Vietnam and will serve as a "bridge" while U.S. manufacturing ramps up, it said in a statement.

The U.S. Commerce Department launched a months-long investigation into whether imports of solar panels from these countries are circumventing tariffs on goods made in China.

The investigation essentially halted the flow of solar panels that make up more than half of U.S. supplies and 80 percent of imports.

U.S. state governors, lawmakers, industry officials and environmentalists have expressed concern over the investigation, which could have led to retroactive tariffs of up to 250 percent.

The issue created a unique dilemma for the White House, which is eager to show U.S. leadership on climate change, in part by encouraging the use of renewable energy, while respecting and keeping its distance from the investigation proceedings.

Using executive action and invoking the DPA, which gives presidents some authority over domestic industries, allows Biden to take advantage of the tools available to him without stepping on the Commerce Department inquiry.

The White House said that, compared to when Biden took office, the U.S. was on track to triple domestic solar manufacturing capacity by 2024, from 7.5 gigawatts to 22.5 gigawatts, enough to enable 3.3 million homes to switch to solar each year.

(With input from agencies)