South Korea has approved a plan to send $8 million worth of aid to North Korea, as China warned the crisis on the Korean peninsula was getting more serious by the day and the war of words between Pyongyang and Washington continued.

North Korea’s foreign minister likened US President Donald Trump to a “barking dog” on Thursday, after Trump warned he would “totally destroy” the North if it threatened the United States and its allies.

Chinese Foreign Minister Wang Yi said the situation on the Korean peninsula was getting more serious by the day and could not be allowed to spin out of control.

“We call on all parties to be calmer than calm and not let the situation escalate out of control,” Wang said, according to a report from the state-run China News Service on Thursday.

Meeting separately with his South Korean counterpart, Kang Kyung-wha, Wang reiterated a call for South Korea to remove the US-built THAAD anti-missile system, which China says is a threat to its own security.

“China hopes South Korea will make efforts to reduce tension,” a report on China’s official Xinhua news agency quoted Wang as saying.

The decision to send aid to North Korea was not popular in South Korea, hitting President Moon Jae-in’s approval rating. It also raised concerns in Japan and the United States, and followed new UN sanctions against North Korea over its sixth nuclear test earlier this month.

The South’s Unification Ministry said its aid policy remained unaffected by geopolitical tensions with the North. The exact timing of when the aid would be sent, as well as its size, would be confirmed later, the ministry said in a statement.

Trump: US will 'totally destroy' North Korea 'if forced to'

The South said it aimed to send $4.5 million worth of nutritional products for children and pregnant women through the World Food Programme and $3.5 million worth of vaccines and medicinal treatments through UNICEF.

“We have consistently said we would pursue humanitarian aid for North Korea in consideration of the poor conditions children and pregnant women are in there, apart from political issues,” said Unification Minister Cho Myong-gyon.

UNICEF’s regional director for East Asia and the Pacific Karin Hulshof said in a statement before the decision the problems North Korean children face “are all too real”.

“Today, we estimate that around 200,000 children are affected by acute malnutrition, heightening their risk of death and increasing rates of stunting,” Hulshof said.

“Food and essential medicines and equipment to treat young children are in short supply,” she said.

The last time the South had sent aid to the North was in December 2015 through the United Nations Population Fund (UNFPA) under ex-President Park Geun-hye.

South Korea’s efforts aimed at fresh aid for North Korea dragged down Moon’s approval rating. Realmeter, a South Korean polling organisation, said on Thursday Moon’s approval rating stood at 65.7 percent, weakening for a fourth straight month.

Although the approval rate is still high, those surveyed said Moon had fallen out of favour due to North Korea’s continued provocations and the government’s decision to consider sending aid to North Korea, Realmeter said.

Moon will meet Japan’s Prime Minister Shinzo Abe and Trump later on Thursday on the sidelines of the UN General Assembly, where North Korea was expected to be the core agenda item.

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In an address on Tuesday, Trump escalated his standoff with North Korea over its nuclear challenge, threatening to “totally destroy” the country of 26 million people if the North threatened the United States and its allies.

Trump also mocked its leader, Kim Jong-un, calling him a “Rocket Man”.

North Korea’s Foreign Minister Ri Yong-ho called Trump’s comments “the sound of a dog barking”.

“There is a saying that goes: ‘Even when dogs bark, the parade goes on’,” Ri said in televised remarks to reporters in front of a hotel near the UN headquarters in New York.

“If (Trump) was thinking about surprising us with dog-barking sounds then he is clearly dreaming,” he said.

Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb Show all 6 1 /6 Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb Photos released by North Korea show Kim Jong-un talking to subordinates next to a device thought to be the new thermonuclear weapon. There is no way of independently verifying the pictures STR/AFP/Getty Images Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb North Korea claims it has successfully tested an advanced hydrogen bomb which could be loaded onto an intercontinental ballistic missile AFP/Getty Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb A diagram on the wall behind Mr Kim shows a bomb mounted inside a cone STR/AFP/Getty Images Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb North Korean leader Kim Jong-Un (C) attending a photo session with participants of the fourth conference of active secretaries of primary organisations of the youth league of the Korean People's Army (KPA) in Pyongyang STR/AFP/Getty Images Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb A new stamp issued in commemoration of the successful second test launch of the "Hwasong-14" intercontinental ballistic missile KCNA via Reuters Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb A new stamp issued in commemoration of the successful second test launch of the "Hwasong-14" intercontinental ballistic missile KCNA via Reuters

Asked by reporters what he thought of Trump calling North Korean leader Kim Jong-un “Rocket Man”, Ri quipped: “I feel sorry for his aides.”

North Korea conducted its sixth and largest nuclear test on 3 September and has launched numerous missiles this year, including two intercontinental ballistic missiles and two other rockets that flew over Japan.

Such provocations have sparked strong disapproval from the international community, especially from the United States and Japan.