President Donald Trump told reporters Thursday that tariffs on China could be raised by another $300 billion if necessary.

“Our talks with China, a lot of interesting things are happening. We’ll see what happens ... I could go up another at least $300 billion and I’ll do that at the right time,” Trump said Thursday, according to Reuters, without giving details on what goods could be targeted.

“But I think China wants to make a deal and I think Mexico wants to make a deal badly,” he said at the Irish airport of Shannon on his way to France for a D-Day commemoration.

Negotiations between Beijing and Washington took a turn for the worse in early May with the increase of tariffs on $200 billion worth of Chinese goods exported to the U.S., and an effective ban on American companies doing business with Chinese telecom giant Huawei.

Beijing responded with tariffs on $60 billion worth of U.S. goods, the announcement of an “unreliable entities list” and a far tougher stance against U.S. requests.

In July last year, Trump indicated that he was willing to slap tariffs on every Chinese good imported to the U.S. should the need arise. “I’m ready to go to 500,” the president told CNBC.

Market sentiment has soured amid the trade tensions, with new threats also directed toward Mexico. Trump wants to impose a 5 percent tariff on all Mexican imports, in a political ploy criticized even by members of his own party.

On Wednesday, the International Monetary Fund said U.S.-China tariffs could cut global economic output by 0.5 percent in 2020, noting that tariffs between the world’s two largest economies would cause some $455 billion in gross domestic product to evaporate.