Negotiators are making progress toward finalizing a partial trade deal between the United States and China, including agreeing on the removal of some of the tariffs that have disrupted trans-Pacific commerce for the past year and a half.

But American and Chinese diplomats still must resolve several core issues before the text is ready for President Trump and Chinese President Xi Jinping to sign, according to people familiar with the talks.

The Dow Jones industrial average on Thursday rose 182 points, or 0.7 percent, amid the positive signals.

Nearly four weeks after Trump said the two sides had reached an “agreement in principle,” the White House and China continue to haggle over terms. Among them: the extent to which the United States will roll back tariffs on Chinese imports as well as specific Chinese pledges to protect the intellectual property and trade secrets of U.S. companies.

Some other provisions are largely complete, including ones that govern currency moves and the opening of China’s financial services market to foreign companies.

“Our understanding is the two sides are very close to an agreement,” said Myron Brilliant, executive vice president for the U.S. Chamber of Commerce. “The timing is still to be determined.”

Hopes for a mid-November signing, however, have been dashed and officials from the two countries are considering alternative options for a signing next month, if the deal is complete by then.

With the president scheduled to attend a North Atlantic Treaty Organization (NATO) summit in London Dec. 3-4, a European venue might make sense. Trump said on Sunday that the signing would take place in the United States, but Chinese officials have not agreed to that.

As the talks intensify, Chinese officials are pushing for additional administration concessions. The president last month called off a planned Oct. 15 increase in U.S. tariffs on $250 billion in Chinese goods after negotiators sketched the outlines of a “phase one” deal.

Trump is believed likely to abandon plans to impose import levies starting Dec. 15 on an additional $160 billion in products, including many popular consumer items such as smartphones and laptop computers.

Chinese officials also want the United States to eliminate the 15 percent tariff that Trump imposed Sept. 1 on about $112 billion in imports. In return, the United States wants China to agree to more extensive intellectual property safeguards, according to two people familiar with the bargaining.

“That decision is wholly and exclusively in the president’s hands,” said one person who had been briefed on the talks, but spoke on the condition of anonymity to describe the confidential discussions.

China’s Commerce Ministry said Thursday that U.S. and Chinese negotiators had agreed in principle to roll back tariffs in simultaneous stages if their trade talks advance.

Gao Feng, the ministry spokesman, said the two countries have held “earnest and constructive” talks.

“If the two parties reach the first-phase agreement, they should, in accordance with the contents of the agreement, simultaneously and proportionally cancel the tariffs that were already raised,” Gao said. “This is an important condition for reaching an agreement.”

Robert E. Lighthizer, the president’s chief trade representative, has been seeking Chinese agreement to an enforcement mechanism that would condition tariff reductions on Chinese implementation of the agreement. Tariffs would fall — or rise — depending upon whether Beijing complied with specific terms, said one person familiar with the talks.

“China’s put a bit of a spin on it,” the person said, referring to the Commerce Ministry statement.

Tariff reductions in the preliminary deal could amount to a bargaining win for Beijing. China has long said that the United States must roll back levies as a condition of a trade deal and has sought a tariff reduction as part of any first step.

“China’s position has been consistent and clear: The trade war was started by raising tariffs, and so it should be ended by canceling them,” Gao told reporters in Beijing.

Earlier on Thursday, China publicized in unusual fashion the sentencing of nine people convicted of trafficking fentanyl to the United States. Trump has long lambasted China for not doing enough to crack down on production of the deadly opioid and suggested that Chinese progress in stemming the flow would be part of what he sought in a broad trade deal.

China has played down its role in the U.S. opioid epidemic and denied that trade concerns motivated its drug-enforcement actions.

Renewed prospects for a deal come as the trade war’s toll is mounting. Tariff hikes are costing the economy 40,000 jobs per month, according to a rough estimate by the Federal Reserve Bank of Atlanta.

In a Fed survey, 20 percent of manufacturers said they had postponed or reduced planned capital investment in the first half of 2019.

The trade war cost the U.S. economy $40 billion in total business investment during that period, double the figure for the last six months of 2018, the bank said.

“The negative effects of trade policy developments on U.S. business activity have grown over time, particularly for firms with an international reach,” the regional Fed bank said.

The trade talks have missed multiple deadlines since Trump and Xi launched them 11 months ago over a steak dinner in Buenos Aires. So while the Commerce Ministry statement lifted hopes that a partial deal may finally be coming into sight, some observers counseled caution.

“What is actually in the agreement is still not clear,” one said. “It is clear that they’re close.”