WASHINGTON — President Trump ordered his chief trade negotiator to consider imposing tariffs on an additional $100 billion of Chinese products Thursday, in a dramatic escalation of his trade war with China.

The threat from Trump is the latest volley between the White House and Beijing in an exchange of trade attacks that continue to broaden in scope and severity.

Trump’s newest move would impose tariffs on a large share of imported Chinese goods that enter the United States — $505.6 billion last year.

It comes a day after China issued a list of tariffs against $50 billion in US goods, including soybeans and small aircraft, in response to recent actions from Trump.

‘‘Rather than remedy its misconduct, China has chosen to harm our farmers and manufacturers,’’ Trump said in a statement Thursday evening.

The president’s latest salvo is certain to spook US allies in Europe and Japan as well as American business leaders, who are desperate for a negotiated resolution of the increasingly acrimonious dispute.

The president’s statement moves the world’s two largest economies, which together account for nearly 40 percent of the global economy, closer to an open brawl.

The stock market was closed when the White House released Trump’s statement about the $100 billion in additional tariffs, but Dow futures tumbled over 300 points, a sign that markets are likely to open down Friday and that Wall Street traders believe a trade war is growing increasingly likely.

The tariffs are not yet in effect, and there is still time for both sides to negotiate, but the announced level of tariffs almost certainly would lead to American and Chinese consumers facing higher prices at stores for many everyday items.

Many in the business community are urging Trump and Chinese President Xi Jinping to reach a settlement before the tariffs go into effect, and Republican lawmakers have been urging the US president to back down.

The lawmakers fear a deepening trade war will hurt jobs and businesses in their states, and they worry it could cost Republican votes in the 2018 midterm elections.

‘‘Hopefully the president is just blowing off steam again, but if he’s even half-serious, this is nuts,’’ Senator Ben Sasse, Republican of Nebraska said in a statement Thursday night.

Trump’s threat of more tariffs comes amid broadening confusion about the White House approach to trade policy, as it is in the midst of a major personnel change, and Trump has taken to issuing statements and decrees on social media only to have them explained in different ways by aides.

Financial markets have wobbled as investors are led by Trump to think that the trade tensions are escalating, and then they are assuaged by another White House official suggesting that things will be resolved peacefully.

One reason for the public confusion is because Trump’s current economic advisers are split into separate camps. White House adviser Peter Navarro has cheered Trump’s adversarial approach to China. Others, particularly National Economic Council Director Larry Kudlow, have suggested that these moves are all part of a grand negotiation that could result with no tariffs taking effect.

But every time aides attempt to soften the edge of Trump’s trade threats, the president takes direct aim at Beijing and declares that he won’t back down until the gap between US imports from China and its exports to that country is dramatically narrowed.