Washington, Jun 21 (IANS): US President Donald Trump has admitted that China has not succeeded in getting North Korea to curb its nuclear and ballistic missile programmes.

Trump's statement, delivered in an almost cavalier tweet on Tuesday, was an extraordinary admission of failure in his strategy for dealing with the North Korean regime of Kim Jong-un, New York Times said.

Given how ardently the US had sought the cooperation of Chinese President Xi Jinping, Trump upended much of that work in 140 characters, tweeting that Chinese efforts have "not worked out".

"While I greatly appreciate the efforts of President Xi and China to help with North Korea, it has not worked out. At least I know China tried," Trump wrote.

The tweet, which came hours before the US and China were set to meet in Washington to talk about North Korea, caught multiple Trump administration officials off guard, leaving them scrambling as they tried to figure out what exactly the President meant, CNN reported.

For months, Trump, Vice President Mike Pence and top aides have staked any progress dealing with North Korea's burgeoning nuclear programme on China's involvement.

Hanging over the Tuesday's tweet -- and Wednesday's meeting -- was the death of Otto Warmbier, an American college student who died on Monday after spending 17 months in detention in North Korea.

His family believes he was tortured into a vegetative state. Trump condemned the "brutal regime" and lamented the loss of a young man "in the prime of life".

Trump had made clear in the past that despite his preference to work with China on North Korea, he was willing to go after them alone, the media reports added.

"I have great confidence that China will properly deal with North Korea. If they are unable to do so, the US, with its allies, will!" he tweeted in April.