EU's Juncker refuses US trade talks 'under threat'

European Commission President Jean-Claude Juncker on Wednesday said the EU would refuse to negotiate on trade with the US while "under threat" from its purported ally.

Juncker sarcastically described as "generous" an eleventh hour decision by US President Donald Trump to spare the European Union from punishing steel and aluminium tariffs for 30 days.

"We consider that the US measures cannot be justified on the basis of national security considerations that have no reason for being among allies," Juncker told a session of European Parliament in Brussels.

"We therefore call for an outright withdrawal. We will continue negotiations with the United States but refuse to negotiate under threat," he added.

The 25 percent tariffs on steel and 10 percent duties on aluminium were set to go into effect on Tuesday, as temporary exemptions granted in March to the EU and other US allies expired.

Europe -- which last year exported over $7.7 billion of steel and aluminium to the US market -- has lined up its own punitive tariffs on American imports, including iconic items like Harley-Davidson motorbikes, blue jeans and bourbon whiskey.

The Trump administration has told trading partners they must make concessions, but the EU has slammed the US intentions as vague and said it will not negotiate without first obtaining a permanent exemption.

The EU earlier expressed disappointment, saying the decision would "prolong uncertainty," and called for a permanent exemption.