Donald Trump attacked China over its trade ties with Pyongyang in an early morning tweet, after his top diplomat warned that any country providing economic or military aid, or hosting North Korean workers, was abetting Kim Jong-un’s regime.
“Trade between China and North Korea grew almost 40% in the first quarter. So much for China working with us – but we had to give it a try,” Trump wrote. He appeared to be referring to data released in April, that showed China had shut down coal imports in line with UN sanctions, but increased purchases of other products.
The US president’s attacks on North Korea’s most important ally are likely to add to tensions at a UN security council meeting on the incident, due to be held at 3pm New York time (1900 GMT), which was called by Washington, Tokyo and Seoul.
China has already called for restraint from all sides, after joining diplomatic forces with Russia to suggest that North Korea suspend its missile programme in return for a moratorium on large-scale US and South Korean military exercises.
That would cover deployments like the live-fire ballistic missile exercise early on Wednesday that officials in Seoul said was intended as a warning to Pyongyang.
The South Korean president, Moon Jae-in, said it would demonstrate the allies’ determination to counter North Korean provocations with deeds and not just words of condemnation. “We need to clearly show our missile defence readiness to North Korea,” the presidential Blue House said in a statement.
The US secretary of state, Rex Tillerson, earlier said any country that supported Pyongyang, hosted workers sending hard currency remittances or failed to implement United Nations sanctions was “aiding and abetting a dangerous regime”.
“Testing an ICBM represents a new escalation of the threat to the United States, our allies and partners, the region, and the world. All nations should publicly demonstrate to North Korea that there are consequences to their pursuit of nuclear weapons,” he said in a statement.
The news agency claimed the North Korean missile was capable of carrying a “large, heavy nuclear warhead” that could survive re-entry into the Earth’s atmosphere.
Kim was quoted as saying the North’s long confrontation with Washington had entered the “final stage” and that Pyongyang would not put its nuclear weapons and ballistic missiles up for negotiation “unless the US hostile policy and nuclear threats come to an end completely”.
A report in its state media said Kim urged his scientists to “frequently send big and small ‘gift packages’ to the Yankees”.
The US and its allies are expected to seek agreement on tougher measures against Pyongyang at the emergency session of the UN security council. Trump and Vladimir Putin are also expected to address growing North Korean provocations at their meeting on the sidelines of the G20 summit in Hamburg on Friday.
China is pushing for talks between world powers and North Korea on dismantling its nuclear programme but the US maintains that Pyongyang must first halt its missile and nuclear tests. .
“Self-restraint, which is a choice, is all that separates armistice and war,” Gen Vincent K Brooks, commander of the US Forces Korea, and Gen Lee Sun-jin, chairman of the South’s joint chiefs of staff, said in a statement.
The South Korean Yonhap news agency quoted Lee as saying South Korea and the US were maintaining “patience and self-restraint” despite the North’s repeated provocations.
Analysis by Japan and South Korea has supported the account given by North Korea’s Academy of Defence Science, which said the missile reached an altitude of 1,741 miles (2,802km) and flew 580 miles. The US initially described it as an intermediate-range missile but now concedes it was an ICBM.
North Koreans have celebrated the ICBM launch in the capital, Pyongyang. A 38-year-old Pyongyang resident named Ri Song-gil said his country “can attack anywhere in the world”. He added: “Now, the time when the US could threaten the world with nuclear weapons has passed away.”
Kim Hye-ok, 27, said the launch was “extremely delightful news”, adding that North Korea “will march forward along our own way” despite international sanctions.
David Wright, a US-based missile expert, estimated that the highly lofted missile could have a possible maximum range of 4,160 miles, which could put Alaska in its range if fired at a normal trajectory.
Hamish de Bretton-Gordon, a former commanding officer of the British Armed Forces Joint Chemical Biological Radiological Nuclear Regiment, said that “in capability of missile terms and delivery, it is a major step up and they seem to be making progress week on week”.
Questions remain about whether the North can miniaturise a nuclear weapon to fit a missile nosecone, or if it has mastered the technology needed for it to survive re-entry into the Earth’s atmosphere.
Some experts believe the North already has the ability to mount warheads on shorter-range missiles that can strike South Korea and Japan, home to dozens of US military bases and about 80,000 US troops.
Jeffrey Lewis, an expert on nuclear non-proliferation, said the US may have to accept that North Korea was close to crossing the “red line” of developing a nuclear weapon that can threaten parts of the US.
“The window for negotiating denuclearization is closed,” Lewis said. “The big point is that we have to accept North Korea with a nuclear-armed ICBM.”