WASHINGTON: US President Donald Trump vowed Thursday to press ahead with 25 percent tariffs on foreign steel and 10 percent on aluminum - singling out Germany for criticism while saying Mexico, Canada, Australia and "others" could be exempt.

"We are going to be very fair, we're going to be very flexible," Trump told his cabinet while pointing to winners and losers from the contentious policy.

Trump said Mexico and Canada could get carve-outs if talks to renegotiate the trilateral NAFTA trade agreement go well.

"If we reach a deal it is most likely that we won't be charging those two countries the tariffs," he said, adding that Australia would also be spared.

"We have a very close relationship with Australia, we have a trade surplus with Australia, great country, long term partner, we´ll be doing something with them," he said. "We'll be doing something with some other countries."

But Trump took aim at Germany - the biggest economy in the EU trade bloc - as a bad actor likely to face tariffs.

Railing against countries that had "taken advantage" of the United States, Trump accused Germany of behaving unfairly by contributing much less than the US towards the funding of NATO.

"We have some friends and some enemies where we have been tremendously taken advantage of over the years on trade and on military," he said.

"If you look at NATO, where Germany pays one percent and we are paying 4.2 percent of a much bigger GDP -- that´s not fair," he said.

"So we view trade and we view the military, and to a certain extent, they go hand in hand."