In one of his sharpest reverses as president, Trump says China is not a currency manipulator.

WASHINGTON — The United States and China struck what appeared to be an unusual bargain Wednesday as President Trump said he won’t label China a currency manipulator and voiced confidence Chinese President Xi Jinping will help him deal with North Korea’s mounting threat.

Another result of the diplomatic wrangling: a surprising Chinese abstention on a U.N. resolution condemning a Syrian chemical weapons attack.

In a newspaper interview and a White House news conference, Trump hailed the rapport he developed with Xi during last week’s Florida summit, which seems to have yielded an immediate easing of tensions related to the U.S.-Chinese trade imbalance and how to prevent Pyongyang from developing a nuclear missile capable of reaching the United States.

“I think he wants to help us with North Korea,” Trump said of Xi, crediting China in the news conference with taking a “big step” by turning back boats of coal that North Korea sells to its northern neighbor. North Korea conducts some 90 percent of its trade with China.

And in one of the sharpest reverses of his presidency, Trump backed off from a campaign pledge by saying he would not declare China to be a currency manipulator, an action that could have led to higher tariffs on Chinese goods. The accusation had formed a basis of Trump’s argument for lost American jobs.

“They’re not currency manipulators,” Trump told The Wall Street Journal earlier Wednesday.