Washington (AFP) - The United States and South Korea held high-level talks Thursday after North Korea test-fired one of its newest and most powerful missiles, demonstrating its threat to the US mainland days ahead of elections.

The weapons test was the first since North Korea was accused of sending troops to Russia to support the invasion of Ukraine, triggering alarm and warnings by Washington, Seoul and European countries.

North Korea’s latest actions were certain to top the agenda as US Secretary of State Antony Blinken and Defense Secretary Lloyd Austin opened previously scheduled joint talks with their South Korean counterparts in Washington.

South Korea, which previously said that the North was preparing a missile or even nuclear test ahead of US elections on Tuesday, said Pyongyang appeared to have fired a solid-propelled long-range ballistic missile.

It flew 1,000 kilometers (621 miles) after being fired on a lofted trajectory – meaning up, not out, the South Korean military said.

Developing advanced solid-fuel missiles – which are quicker to launch and harder to detect and destroy in advance – has long been a goal for North Korean leader Kim Jong Un.

Kim called the sanctions-defying launch “an appropriate military action that fully meets the purpose of informing the rivals… of our counteraction will,” according to the official Korean Central News Agency.

The test “updated the recent records of the strategic missile capability,” of North Korea, the agency said, with Kim vowing his country “will never change its line of bolstering up its nuclear forces”.

- Longest-ever launch -

Tokyo said that the “ICBM-class” missile had flown for longer than any other previously tested by the North, being airborne for about 86 minutes and hitting altitudes of 7,000 kilometers.

“We estimate that its flying altitude was the highest we have seen,” Japanese Defense Minister Gen Nakatani told reporters.

Blinken and his South Korean and Japanese counterparts discussed the launch in a joint telephone call, issuing a statement afterward urging North Korea to end its “provocative and destabilizing actions.”

Both the White House and UN Secretary-General Antonio Guterres said that the launch clearly violated UN Security Council resolutions.

The missile could in theory strike the mainland United States, although that country’s National Security Council spokesman Sean Savett said there was no immediate risk from the test-firing.

China, historically North Korea’s closest ally, said it was “concerned about developments on the (Korean) peninsula” and urged a “political resolution” to the issue.

- Ukraine outrage -

The United States has said that around 10,000 North Korean troops have made their way into Russia with a small number in the Kursk region on the Ukrainian border.

Ukrainian President Volodymyr Zelensky, speaking to South Korean media, denounced what he called inaction by his allies and said he was surprised by the “silence” of China.

“I think that the reaction to this is nothing; it has been zero,” Zelensky said.

The United States has warned North Korea over the deployment, with an envoy saying Wednesday that the troops will “return in body bags” if they cross into Ukraine.

South Korea has said it is reviewing whether to send weapons directly to Ukraine in response, an idea it has previously resisted due to longstanding domestic policy that prevents it from sending weaponry into active conflicts.

North Korea’s missile launch “seems to have been carried out to divert attention from international criticism of its troop deployment,” said Yang Moo-jin, president of the University of North Korean Studies in Seoul.

Seoul has warned that Russia may be providing new technology or expertise to Pyongyang in return for weapons and troops to help them fight Ukraine.

It is possible “Russia actually provided new technology for reentering the atmosphere,” said Ahn Chan-il, a defector-turned-researcher who runs the World Institute for North Korea Studies.

But it is more likely that Thursday’s test was a bid to distract from the troop deployment and get “the world’s attention ahead of the US presidential election,” Ahn added.

Vice President Kamala Harris in a campaign rally Tuesday charged that Kim and Putin “are rooting” for her rival Donald Trump as he is “easy to manipulate with flattery and favor.”

Trump as president met three times with Kim, unusually personal diplomacy that reduced tensions but did not yield a lasting agreement.

North Korea has denied sending troops to Russia, but in the first comment in state media last week, its vice foreign minister said that if such a deployment were to happen, it would be in line with international law.

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