WASHINGTON — The Trump administration is close to a trade deal with China that would roll back tariffs on both sides of the Pacific but may do little to achieve the substantive changes to China’s economy that the United States initially set out to win, people with knowledge of the talks said.

Significant details remain unsettled and the deal is still being discussed but so far, the two sides have agreed on a pact that would largely require Beijing to make big purchases of American agricultural and energy goods and to lower some barriers that prevent American companies from operating in China. In return, the United States would most likely drop its tariffs on at least $200 billion of the $250 billion worth of Chinese imports currently subject to American levies.

China, which has retaliated against President Trump’s tariffs with its own punishing taxes on American goods, is pushing for the elimination of all of the Trump tariffs, a person with knowledge of the negotiations said. It is unclear whether the Trump administration will agree to remove all the tariffs or keep some in place to keep pressure on China. As part of the agreement, the Trump administration has been pushing China to accept an enforcement mechanism that would enable the United States to quickly reinstate tariffs if Beijing fails to live up to specific promises.

For Mr. Trump, the ability to announce a deal with China would constitute a victory for a presidency rocked by legal investigations and failed nuclear disarmament talks with North Korea last week. Mr. Trump has spent more than a year accusing China of unfair trade practices and promising to shift the balance of economic power back to the United States.