WASHINGTON

President Donald Trump, plainly frustrated by China’s inaction on North Korea, aimed his Twitter feed at Beijing on Tuesday, telling the Chinese government that the United States would exchange trade concessions for support in pressuring Pyongyang.

“I explained to the President of China that a trade deal with the US will be far better for them if they solve the North Korean problem!” Trump declared on Twitter around 8am. EST.

That was followed by a more impatient post in which he said: “North Korea is looking for trouble. If China decides to help, that would be great. If not, we will solve the problem without them! USA.”

Trump’s message captures his quandary in dealing with the nuclear threat from North Korea: Only China, with its economic leverage over its neighbour, can realistically force a change in the behaviour of North Korea’s dictator, Kim Jong Un.

President Xi Jinping of China did not offer Trump any public commitments when they met last week in Palm Beach, Florida. Even in private conversations, officials said, the Chinese leader was circumspect.

Still, Trump’s explicit linkage of North Korea and trade suggested that the president was more likely to seek a bargain with China than to proceed unilaterally. Under pressure from the United States on trade, China proposed a 100-day plan during the summit meeting that would overhaul the trade relationship between the two countries.

In his first concrete move on trade, Trump plans to sign an executive order targeting countries that dump steel into the US market, a measure that would be aimed mainly at China.

But it is not yet clear which side has the initiative in the evolving debate over trade. During his meeting with Xi, administration officials said, Trump warned that China needed to address its yawning trade imbalance with the United States immediately. But the Chinese did not bring any trade-related gestures to the meeting, as some experts expected.

Instead, they countered with the proposal for the 100-day plan. The United States embraced the idea, though the commerce secretary, Wilbur L. Ross, noted that the plan would have “way stations” to measure progress, suggesting that the administration is not willing to wait the full 100 days for results.

Trump’s threat to act unilaterally against North Korea was not new. But a military attack on the country would be a far more complex and risky undertaking than the strike on Syria, given the North’s nuclear ability and missile arsenal, and its proximity to huge population centers in South Korea.

With China, in particular, Trump has shown an inclination to pursue a transactional approach to policy. Last December, he suggested that he would use the US relationship with Taiwan, which China views as a renegade province, as another bargaining chip in the relationship.