President Donald Trump said Thursday that tariffs on Chinese and Mexican imports would move forward on March 4 and that he would add an additional 10% levy on China, heightening the stakes of his trade battle that has rattled Wall Street and injected an air of uncertainty during his first weeks in office.

In a post on Truth Social, Trump framed his decision to move forward with the tariffs as a response to “unacceptable levels” of drugs coming into the US from Canada and Mexico and supplied by China.

“We cannot allow this scourge to continue to harm the USA, and therefore, until it stops, or is seriously limited, the proposed TARIFFS scheduled to go into effect,” he wrote, would begin next week.

His comments appeared to clarify remarks he made Wednesday afternoon during a cabinet meeting, when Trump had suggested the tariffs on Mexico and China would begin in April. His latest post reiterates that the levies are scheduled to be implemented in the coming days.

Trump’s tariff threats have weighed down public sentiment. Consumers increasingly see that coming tariffs could lead to higher prices, as suppliers pass on the cost of the levies to American shoppers. Two recent consumer sentiment surveys showed a souring outlook. In turn, Wall Street has pulled back, delivering a batch of down days, and prompting questions of a potential market correction and slowing growth.

Trump’s style of negotiating, in which the threat of tariffs are used as a means to extract policy concessions, has also added to global uncertainty.

In recent weeks, investors offered a muted reaction to Trump’s tariff pronouncements. Analysts have said Wall Street is weighing whether the levies will actually be implemented, and if, as the deadline approaches, the White House would pull back on the severity and scope of the tariffs.

The duties were originally scheduled to take effect earlier, but Trump agreed to a monthlong delay after the leaders of Mexico and Canada committed to stronger security measures at the US border. The back-and-forth, tit-for-tat dealmaking has added to the element of confusion and unease.

The run-up to next week’s tariff execution date will likely deliver another dose of volatility to the market.

Trump has signaled his trade battle won’t be confined to North American trading partners. During the cabinet meeting, he threatened new tariffs on the European Union, describing the bloc as an adversary to the US.

“We’ll be announcing it very soon, and it’ll be 25% generally speaking, and that’ll be on cars and all of the things,” he said.