U.S. President Donald Trump said Thursday a "major conflict" with North Korea is possible in the standoff over the country's nuclear and missile programs, but that he would like to address the issue through diplomatic means.

"There is a chance that we could end up having a major, major conflict with North Korea. Absolutely," Trump told Reuters news agency. "We'd love to solve things diplomatically but it's very difficult."

The remarks came a day before the U.N. Security Council convenes a meeting on North Korea at which the United States will seek to step up pressure on the country with allies such as Japan and South Korea and regional partners including China, a longtime benefactor and by far the biggest trade partner of the North.

In an interview with Fox News the same day, U.S. Secretary of State Rex Tillerson said China has warned North Korea it will impose punitive measures if Pyongyang conducts another nuclear test.

"We were told by the Chinese that they informed the (North Korean) regime that if they did conduct further nuclear tests, China would be taking sanctions actions on their own," he said.

Tillerson did not say what kind of sanctions China may have in mind, and nor did he say when Beijing issued its warning to Pyongyang. It would likely be the strongest threat yet to its defiant neighbor.

Tillerson told Fox News that U.S. intelligence reports suggest North Korean leader Kim Jong Un is "not crazy."

"He may be ruthless, he may be a murderer. He may be someone who in many respects we would say by our standards is irrational," the top U.S. diplomat said. "But he is not insane."

In a meeting with Chinese Foreign Minister Wang Yi on the sidelines of the Security Council meeting, Tillerson will request that China use its "unique leverage" over Kim so as to "convince or compel North Korea to rethink its strategic calculus," a State Department spokesman said.

China accounts for about 90 percent of North Korea's trade and is a major supplier of oil for the country. Washington and other countries have urged Beijing to exercise its considerable influence over Pyongyang to curb its growing nuclear and missile threats.

The Trump administration has called for exerting "maximum pressure" on North Korea through sanctions and diplomatic activity while remaining open to negotiations for removing its nuclear weapons.

Senior administration officials have said "all options are on the table," including military options.

Aside from a push on China to play a larger part in reining in the Kim regime, Tillerson will tell Wang that the United States seeks the peaceful denuclearization of the Korean Peninsula, and that Washington remains open to negotiations with Pyongyang toward that goal, according to the State Department.

"One of the things that the secretary (Tillerson) is going to try to build through his meetings tomorrow in New York is the sense that the global community, as a whole, needs to stand up to North Korea and needs to apply pressure on North Korea," department spokesman Mark Toner said at a press briefing on Thursday.

"Certainly, we've talked a lot about China's role, significant role in that and that's a key aspect of this new strategy, is putting pressure on China, convincing China they need to do more, but this also needs to be a global effort," Toner said.

Separately, Tillerson will have a meeting Friday with Japanese Foreign Minister Fumio Kishida and South Korean Foreign Minister Yun Byung Se to affirm increased trilateral coordination over North Korea.

==Kyodo