WASHINGTON — Accusing Beijing of “reneging” on commitments it made in earlier talks, the nation’s top trade negotiator said Monday that the Trump administration will increase tariffs on $200 billion in Chinese goods Friday, a sharp escalation in a yearlong trade dispute.

At the same time, a Chinese trade delegation is expected to arrive in Washington to resume negotiations on Thursday, a day later than originally planned.

At a briefing with reporters, neither U.S. Trade Representative Robert Lighthizer nor Treasury Secretary Steven Mnuchin offered details of China’s alleged backsliding, and there was no immediate response from Beijing.

Mnuchin said Trump officials learned over the weekend that Chinese officials “were trying to go back on some of the language” that had been negotiated in 10 earlier rounds of talks.

The U.S. officials said that at 12:01 a.m. Eastern time Friday, the administration will raise the tariffs from 10 percent to 25 percent. President Donald Trump had announced those plans via Twitter on Sunday, expressing frustration with the pace of negotiations. The hit list includes such varied products as baseball gloves, vacuum cleaners and burglar alarms.

The reiteration Monday of the president’s threat from high-level Trump officials reinforced the administration’s determination to put Beijing on the defensive.

By threatening to raise taxes on Chinese imports, Trump is throwing down a challenge to Beijing: Agree to sweeping changes in China’s government-dominated economic model — or suffer the consequences.

The unexpected ultimatum shook up financial markets, which had expected the world’s two biggest economies to resolve a yearlong standoff over trade, perhaps by the end of the week.

“It’s a significant change in the president’s tone,” said Timothy Keeler, a partner at the law firm Mayer Brown and former chief of staff for the U.S. Trade Representative office. “It certainly increases the possibility that you’ll have no deal.”

For weeks, Trump administration officials had been suggesting that the U.S. and Chinese negotiators were making steady progress.

Suddenly on Sunday, Trump said he had lost patience: “The Trade Deal with China continues, but too slowly, as they attempt to renegotiate. No!” he tweeted.

Trump also said he planned “shortly” to slap 25 percent tariffs on another $325 billion in Chinese products, covering everything China ships to the United States.

The two countries are engaged in high-stakes commercial combat over China’s aggressive push to establish Chinese companies as world leaders in cutting-edge fields such as robotics and electric vehicles.

The United States accuses Beijing of predatory practices, including hacking into U.S. companies’ computers to steal trade secrets, forcing foreign firms to hand over technology in exchange for access to the Chinese market and unfairly subsidizing Chinese firms at the expense of foreign competitors.