Europe must respond to US President Donald Trump's new tariffs on steel and aluminum with a united voice if its eventual counter-measures are to have an impact, French Finance Minister Bruno Le Maire said on Friday.

Trump pressed ahead on Thursday with import tariffs of 25 percent on steel and 10 percent for aluminum but exempted Canada and Mexico and offered the possibility of excluding other allies.

Le Maire said on Thursday evening there would only be "losers" in a trade war resulting from tariffs imposed by Washington.

PARIS (Reuters) - Europe must respond to U.S. President Donald Trump's new tariffs on steel and aluminum with a united voice if its eventual counter-measures are to have an impact, French Finance Minister Bruno Le Maire said on Friday.

Trump pressed ahead on Thursday with import tariffs of 25 percent on steel and 10 percent for aluminum but exempted Canada and Mexico and offered the possibility of excluding other allies, backtracking from an earlier "no-exceptions" stance.

European Union Trade Commissioner Cecilia Malmstrom responded the EU did not believe tariffs were a solution to the problem of overcapacity in the steel sector and that it stood ready to go to the World Trade Organisation if necessary.

"Our reaction must be a collective one if we want it to be effective," Le Maire told reporters.

"The European Commission has said that all options are on the table. The first thing to do is evaluate the impact of the U.S. decision on European industries ... and see what are the measure we will be able to take," he said.

He is to meet representatives of the industry on Monday in Brussels.

Le Maire said on Thursday evening there would only be "losers" in a trade war resulting from tariffs imposed by Washington.