President Donald Trump said Thursday he is "very disappointed" following a report that China may have run afoul of international sanctions by providing oil to North Korea.
In a tweet, Trump warned that "there will never be a friendly solution" to North Korea's nuclear and missile programs "if this continues to happen!"
A South Korean newspaper reported that Chinese and North Korean ships linked up at sea to provide oil to Kim Jong Un's regime. The report comes as the United Nations tries to choke off most of Pyongyang's oil supply amid continued aggressive actions by North Korea.
China has denied illegally providing oil, according to Reuters.
"The situation you have mentioned absolutely does not exist," Chinese Defense Ministry spokesman Ren Guoqiang said at a briefing, according to the wire service.
It is unclear whether Trump's information about the alleged oil sales came from U.S. intelligence or from news reports.
The international community aims to use economic measures to deter North Korea's nuclear and missile programs amid a string of tests this year. Getting China — Pyongyang's only major ally — to cut off resources is a major part of that strategy.
However, the United States, South Korea and Japan have suspicions that China is not fully enforcing international sanctions, according to Reuters.
New sanctions imposed last week by the U.N. Security Council seek to block nearly 90 percent of refined petroleum exports to North Korea.
Later Thursday, Trump shared a video that features him talking about the threat of a nuclear-armed North Korea on NBC's "Meet the Press" 18 years ago. "I've been saying it for a long, long time," the president tweeted.