FILE PHOTO: A worker cuts a piece from a steel coil at the Novolipetsk Steel PAO steel mill in Farrell, Pennsylvania, U.S., March 9, 2018. REUTERS/Aaron Josefczyk/File Photo

GENEVA (Reuters) - Switzerland has launched a complaint at the World Trade Organization against U.S. tariffs on steel and aluminum, it said on Tuesday, the eighth WTO member to start such a challenge.

“From Switzerland’s point of view, the additional duties, which according to the U.S. have been introduced to protect national security, are unjustified,” the statement from the Swiss economy ministry said in a statement.

Under WTO rules, the United States has 60 days to settle the issue. After that time, Switzerland could escalate the dispute by asking the WTO to set up a panel of judges to adjudicate.