The United States' threat to impose steep new tariffs on imports from the European Union and Mexico has sparked widespread concern, with leaders and experts warning the move risks deepening global trade tensions and hurting economic stability.

US President Donald Trump announced on Saturday that the country will levy 30 percent tariffs on EU and Mexican goods, starting Aug 1. The tariffs were outlined in letters addressed to European Commission President Ursula von der Leyen and Mexico's President Claudia Sheinbaum, which Trump posted on his social media platform.

In the letters, Trump warned that countries should not retaliate and suggested tariff rates could be adjusted if they cooperate. Similar messages have been sent to more than 20 other US trading partners in recent days, with tariffs ranging from 20 to 50 percent.

In response, von der Leyen said the EU remains open to talks but will defend its interests, while Mexico's government described the move as "unfair treatment", and said talks with Washington are underway.

Dick Schoof, prime minister of the Netherlands, voiced strong concern about the decision. "The US announcement of 30 percent tariffs on goods imported from the EU is concerning and not the way forward," he wrote on social media platform X. "The European Commission can count on our full support. As the EU we must remain united and resolute in pursuing an outcome with the US that is mutually beneficial."

Michael Schumann, president of the Federal Association for Economic Development and Foreign Trade in Germany, told China Daily the tariff threat shows how US trade diplomacy is now shaped by pressure and leverage. "But Europe would be ill-advised to respond with alarm," he said. "Negotiating under duress rarely leads to fair or lasting outcomes.

"The US remains the EU's largest trading partner, but under the Trump administration, this partnership has become a point of strategic exposure. Europe's continued fixation on a fading transatlantic order risks delaying the strategic recalibration it urgently needs."

Europe's core challenge lies within. Without internal cohesion and the will to act in its own interest, it will remain on the defensive, Schumann said, pointing out that reducing vulnerabilities, reindustrializing key sectors, and designing a trade policy that diversifies risks and is fit for a multipolar era, must now take priority.

Duan Demin, a professor of European studies at Peking University, said the move is another example of maximum-pressure tactics of the US.

"By triggering a trade war that targets virtually the entire world, the US now wants to make the EU and Mexico serve as cautionary examples," he said. "But the US should know the world doesn't bend just because it says so. What it really hopes is that the EU and Mexico will yield under this pressure, allowing the US to claim a symbolic victory at home and shore up Democrats' base of supporters.

"For Europe, the possibility of compromise is real — and far from negligible. European leaders know that conceding some ground to the US might help prevent greater economic damage, not least because they still depend heavily on access to the vast US market."

Schumann also said that China has maintained a remarkably stable posture toward Europe and repeatedly signaled its interest in a constructive partnership, encouraging the EU to keep a good economic relationship with China.