The EU's retaliatory tariffs on US exports have been delayed again, European Commission President Ursula von der Leyen has announced.

The countermeasures, which were due to start on Tuesday, came in response to US President Donald Trump's initial import taxes on steel and aluminium.

The EU's retaliation, which would have hit € 21bn worth of US goods, was first suspended in March. This break has been extended until early August, von der Leyen told a press conference on Sunday.

EU trade ministers are expected to meet in Brussels on Monday to discuss how to respond.

It comes after Trump wrote a letter to von der Leyen announcing his plans to impose 30% tariffs on EU imports from 1 August.

He warned that if the trade partner retaliated with import duties of their own against the US, he would hit back by raising tariffs above 30%.

In a pre-recorded interview with Fox News which aired on Saturday night, Trump said some countries were "very upset now" but he insisted the tariffs meant "hundreds of billions of dollars" were "pouring in".

Von der Leyen told journalists on Sunday: "The United States has sent us a letter with measures that would come into effect unless there is a negotiated solution, so we will therefore also extend the suspension of our countermeasures until early August.

"At the same time, we will continue to prepare for the countermeasures so we're fully prepared."

The European Commission president insisted that the EU has "always been very clear that we prefer a negotiated solution".

"This remains the case, and we will use the time that we have now till August 1," she added.

'Defend European interests'

EU trade ministers are set to meet on Monday in Brussels to discuss how strong a line to take with Washington.

Germany's finance minister Lars Klingbeil said on Sunday that "serious and solution-oriented negotiations" with the US were still necessary, but added that if they fail, the EU would need "decisive countermeasures to protect jobs and businesses in Europe".

"Our hand remains outstretched but we won't accept just anything," Klingbeil told daily newspaper Sueddeutsche Zeitung.

His comments came after French President Emmanuel Macron on Saturday urged the European Commission - which negotiates on behalf of all EU countries - to "resolutely defend European interests".

As of Saturday, the Trump administration has now proposed tariff conditions on 24 countries and the EU, which is composed of 27 countries.

On 12 April, White House trade adviser Peter Navarro set a goal to secure "90 deals in 90 days".

So far, the president has announced the outlines of two such pacts with the United Kingdom and Vietnam as negotiations with others continue.