The European Union has called on US President Donald Trump’s administration to stop threatening it with tariffs on steel and aluminium, saying it is prepared to discuss trade – but not at gunpoint.

In March, Mr Trump slapped tariffs of 25% on steel imports and 10% on imported aluminium, but granted the 28 EU countries a temporary exemption until June 1.

He also temporarily exempted big steel producers Canada and Mexico, provided they agree to renegotiate a North American trade deal to his satisfaction.

“It’s Europe’s economic sovereignty, and what we are demanding is that we are exempted without conditions or time limits,” said French President Emmanuel Macron in Bulgaria, where EU leaders have gathered for a summit with Balkans countries.

Convinced that the US move breaks global trade rules, the EU has drawn up a list of “rebalancing” duties worth some 2.8 billion euros to impose on US products if it is not permanently exempt. It has vowed not to negotiate under threat.

“I don’t think we have to consider this or that, when it contravenes the laws of international trade,” Mr Macron said.

But he added: “We can improve things, in a peaceful setting.”

German Chancellor Angela Merkel echoed his remarks.

“We have a common position: We want an unlimited exemption, but are then prepared to talk about how we can reciprocally reduce barriers for trade,” she told reporters in the Bulgarian capital Sofia.

Should the exemptions be dropped, the EU stands ready to deepen transatlantic energy cooperation, notably on liquefied natural gas, improve reciprocal market access for industrial products and work together to reform the rules of the World Trade Organisation.

The EU rejects Mr Trump’s assertion that the tariffs are needed for US national security and sees them as protectionist measures meant to boost local businesses.

Most EU countries are US allies in the world’s biggest security organisation, Nato.