China unveiled retaliatory tariffs of 84% on imports of US goods on Wednesday, matching additional tariffs imposed by US President Donald Trump earlier in the day and further inflaming a trade war between the world’s two biggest economies.

Trump’s sweeping “reciprocal” tariffs took effect earlier on Wednesday. China was the hardest-hit nation, with a levy now totaling at least 104% on all its goods. The two countries have been involved in a game of tit-for-tat on trade, with Beijing standing firmly against each new tariff introduced by Washington.

The trade war widened further on Wednesday after the European Union announced it would begin collecting retaliatory duties on US imports starting Tuesday.

Announcing China’s response, the State Council Tariff Commission said in a statement: “The US escalation of tariffs on China is a mistake upon mistake, severely infringing upon China’s legitimate rights and interests, and seriously damaging the multilateral trading system based on rules.”

The amped-up retaliation comes after China repeatedly warned that it would “fight to the end” if the US moved forward with further tariffs.

On Wednesday, Trump’s additional levies on Chinese imports had originally been set to increase by 34 percentage points. But the president tacked on another 50 percentage points after Beijing refused to back down from the standoff. Prior to the most recent rounds of escalation, Trump had already imposed 20% levies on China.

The back-and-forth between the superpower economies has led to swings in stock markets globally, with Asian and European markets mostly lower and US stocks opening mixed.

“This is getting so ridiculous that it’s hard to believe it’s actually happening between the two largest economies that make up almost $50 trillion of global GDP, almost half of the world – let alone a tariff war against the whole world,” Peter Boockvar, chief investment officer of Bleakley Financial Group, wrote in a research note.

In addition to the increased tariff levy, China’s Ministry of Commerce imposed export controls on 12 American companies, barring Chinese companies from supplying them with dual-use items that have both military and civilian applications.

It also added six more US firms to its “unreliable entity list,” banning them from trading or making new investments in China, and filed a complaint to the World Trade Organization over the latest US tariffs.

US Treasury Secretary Scott Bessent has shrugged off China’s retaliatory moves, telling Fox Business on Wednesday that it is unfortunate that China does not “want to come and negotiate” a tariff deal. He called China the “worst offenders in the international trading system.”

“They have the most imbalanced economy in the history of the modern world, and I can tell you that this escalation is a loser for them … They’re the surplus country,” Bessent said. China’s “exports to the US are five times our exports to China. So, they can raise their tariffs. But so what?”

The EU announcement on Wednesday was in response to a sharp increase in US tariffs on all imports of steel and aluminum, unveiled last month.

“These countermeasures can be suspended at any time, should the US agree to a fair and balanced negotiated outcome,” the European Commission said.