Solar panel installation on the roof of a home in Gainesville, Florida.

South Korea said on Tuesday the government will complain to the World Trade Organization (WTO) about a U.S. decision to slap tariffs on imported washing machines and solar panels, saying the decision is "excessive" and "regrettable".

"It is clear that the latest safeguard measures would violate the WTO rules," South Korea's trade minister Kim Hyun-chong said in a meeting with industry officials. "We will actively respond to protectionist measures."

President Donald Trump slapped steep tariffs on imported washing machines and solar panels on Monday, marking his first moves to erect trade restrictions under seldom-used trade laws that allow unilateral actions.