Seoul (AFP) - North Korean leader Kim Jong Un oversaw a test of Pyongyang’s newest intercontinental ballistic missile with his daughter in tow for the first time, state media reported Saturday.

Declaring he would meet perceived US nuclear threats with nukes of his own, Kim supervised the launch on Friday of the black-and-white missile, the official Korean Central News Agency (KCNA) said was the Hwasong-17 – dubbed the “monster missile” by analysts.

The launch was successful, KCNA said, adding that the “test-fire clearly proved the reliability of the new major strategic weapon system”.

KCNA said Kim attended the launch “together with his beloved daughter and wife”, and state media images showed a beaming Kim accompanied by a young girl in a puffer jacket and red shoes as he walked in front of the missile.

Pyongyang’s state media has never mentioned Kim’s children Kim’s children, and this was the first official confirmation that he had a daughter, experts said.

The latest launch shows that “the nuclear forces of the DPRK have secured another reliable and maximum capacity to contain any nuclear threat”, KCNA said, using the country’s official name, the Democratic People’s Republic of Korea.

Since Kim declared North Korea an “irreversible” nuclear state in September, Washington has ramped up regional security cooperation, including its largest-ever joint air exercises with South Korea.

The South Korean military said it staged joint air drills with the United States on Saturday involving the US B-1B long-range heavy bomber – which was deployed to the Korean peninsula for a separate joint exercise earlier this month.

- Daughter’s debut -

Kim slammed what he called “hysteric aggression war drills” and said that if America continued to make threats against the North, Pyongyang would “resolutely react to nukes with nuclear weapons and to total confrontation with all-out confrontation,” KCNA reported.

North Korea has conducted a record-breaking blitz of launches in recent weeks, which Pyongyang – and Moscow – have repeatedly blamed on US moves to boost the protection it offers allies Seoul and Tokyo.

The presence of the country’s first family provided “greater strength and courage in the dynamic advance for bolstering up the state nuclear strategic forces”, KCNA reported.

KCNA said the missile hit a maximum altitude of 6,040.9 kilometres (3,750 miles) and flew 999.2 kilometres, matching estimates by Seoul and Tokyo on Friday.

North Korea previously claimed to have launched a Hwasong-17 – its most powerful missile to date – on March 24, releasing a slick promotional video and photos of the event.

But Seoul later cast doubt on that claim, with local reports suggesting the Hwasong-17 had exploded over the skies of Pyongyang on March 17, and that the North had faked a successful launch using a smaller, older missile.

This time, analysts said it seemed the North had succeeded.

“This launch is significant because it is thought to be the first successful full flight test of the Hwasong-17 ICBM,” Joseph Dempsey, a researcher at the International Institute for Strategic Studies (IISS) told AFP.

As with all North Korean ICBM tests, the missile was fired on a “lofted” trajectory – up not out, to avoid flying over Japan – which means key questions remain – “particularly in terms of surviving reentry into the atmosphere and testing the accuracy over greater ranges,” he said.

The “monster missile”, despite likely having greater payload capacity, also has disadvantages, Dempsey said.

“Its sheer size makes it less practical as a road-mobile system, and production would be likely a significantly greater strained on limited resources,” he said.

The UN Security Council on Saturday said it would discuss the nuclear-armed country in a Monday meeting.

- Next generation of Kims -

North Korea has fired scores of ballistic missiles this year, far more than any other year on record.

Recent launches have been increasingly provocative, including the firing of a missile over Japan last month, triggering a rare air raid warning.

On November 2, Pyongyang fired 23 missiles, including one that crossed the de facto maritime border and landed near the South’s territorial waters for the first time since the end of hostilities in the Korean War in 1953. Seoul called it “effectively a territorial invasion”.

The next day, North Korea fired an ICBM – although Seoul said it appeared to fail mid-flight.

The most significant takeaway from Friday’s ICBM launch is “the permanence of the Kim regime’s weapons programme, because it is so integral to Kim’s own survival and the continuity of his family’s reign,” Soo Kim, a former CIA analyst now with the RAND Corporation, told AFP.

With the state media coverage, “we have seen with our own eyes the fourth generation of the Kim family. And his daughter – along with potential other siblings – will surely be groomed by her father”, she said.