US President Donald Trump has warned the Chinese leader that the United States is prepared to act on its own in increasing pressure on North Korea, as Washington loses patience with Beijing’s unwillingness to push Pyongyang to abandon its nuclear and missile programs, US officials say.

Trump’s warning was delivered in a blunt phone call on Monday to President Xi Jinping, according to senior White House officials.

Trump took to twitter on Tuesday to express his outrage over the North’s test-firing of a ballistic missile that landed in the Sea of Japan earlier in the day.

“North Korea has just launched another missile. Does this guy have anything better to do with his life?” Trump said of North Korean leader Kim Jung-un, who has pledged to continue the tests and defend his country against the US.

“Hard to believe that South Korea and Japan will put up with this much longer. Perhaps China will put a heavy move on North Korea and end this nonsense once and for all!” he wrote in another tweet.

Pyongyang has drawn warnings from the US and Japan for firing rockets near Japanese territorial waters in the past.

The latest launch came just hours after Trump and Japanese Prime Minister Shinzo Abe agreed over the phone to exert added pressure on North Korea over its missile and nuclear development programs.

They also agreed to hold trilateral talks on the “the growing threat” of Pyongyang's nuclear activities with South Korean President Moon Jae-in on the sidelines of the Group of 20 summit in Germany, which begins on Friday.

On Tuesday, China urged for calm and restraint after the ballistic missile launch. Speaking at a daily news briefing, China’s Foreign Ministry spokesman Geng Shuang said UN Security Council resolutions had clear rules on North Korea's missile launches and Beijing opposed it going against those rules.

A South Korean soldier watches a television news showing file footage of a North Korean missile launch, at a railway station in Seoul, July 4, 2017. (Photo by AFP)

The Trump administration has been pressuring China—the North’s main trade ally—to use its influence over Pyongyang and stop the unruly neighbor’s development of nuclear and ballistic deterrents.

In April, Trump hosted Xi in his private Florida estate of Mar-a-Lago, where he promised the Chinese leader to make his best effort to build strong relations between the two sides in exchange for a tough stance against North Korea.

However, things did not work out the way Trump wanted as he admitted last month that Xi and his government had tried but failed to curb Pyongyang’s military programs.

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Some experts say the United States has refused to deescalate tensions on the Korean Peninsula in order to maintain its military bases in East Asia and contain China.

Last week, American officials said the Pentagon had finished revising its military options against North Korea and will soon present them to Trump.

The Trump administration’s focus on North Korea is nothing short of an obsession, a point that can be inferred from the words of CIA Director Mike Pompeo.

"I hardly ever escape a day at the White House without the President asking me about North Korea and how it is that the United States is responding to that threat," Pompeo told MSNBC in late June. "It's very much at the top of his mind."