US President Donald Trump has warned that the US will not hesitate to take unilateral action against North Korea unless China plays its part and puts pressure on the hermit regime in Pyongyang.

In an interview with the Financial Times, Trump made it clear that he would "deal with North Korea with or without China's help".

He said that it was "totally" possible for the US to tackle North Korea without China.

The increasing threat posed by North Korea's Supreme Leader Kim Jong-un's nuclear programme will be brought up by Trump when he meets Chinese President Xi Jinping at Mar-a-Lago on 6 and 7 April.

It will be the first meeting between the two world leaders.

"China has great influence over North Korea. And China will either decide to help us with North Korea or they won't," he said. "If they do that will be very good for China and if they don't it won't be good for anyone."

When asked if he would consider a "grand bargain" whereby China pressures North Korea in exchange for a guarantee that the US would remove its troops from the Korean peninsula, Trump's response was: "Well, if China is not going to solve North Korea, we will. That is all I am telling you."

There was no immediate reaction from South Korea.

In a separate interview with ABC's This Week, US ambassador to the United Nations, Nikki Haley, said: "The only country that can stop North Korea is China and they know it.

"We're going to continue to put pressure on China to have action." Current sanctions against North Korea over its nuclear and missile programme were insufficient, she added.

"At some point, we need to see definitive actions by China condemning North Korea and not just calling them out for it," she said.

Tensions in the region have risen sharply over recent months after Pyongyang stepped up its ballistic missile tests, with Kim boasting that his country was in the final stages of developing an intercontinental ballistic missile.

In early March, a missile test saw one land close to Japan, resulting in Trump reiterating his country's commitment to "deter and defend against North Korea's ballistic missiles using the full range of United States military capabilities".