North Korea's decision to fire a ballistic missile on Wednesday, a day after agreeing to resume talks with the United States over its nuclear weapons programme, was most likely intended as way to increase its bargaining power with both Washington and Beijing, observers say.

A "new-type SLBM [submarine-launched ballistic missile] Pukguksong-3" was fired from a location near Wonsan Bay, off the nation's east coast in "vertical mode", North Korean state news agency KCNA, said.

The test "had no adverse impact on the security of neighbouring countries" but "ushered in a new phase" in the country's self-defence capabilities, it said.

In South Korea, the Joint Chiefs of Staff said in a statement on Thursday that the missile flew about 450km (280 miles) at a maximum altitude of 910km after lift-off from an unspecified place in waters off the North Korean coastal town of Wonsan.

The launch came just hours after Pyongyang announced it would resume nuclear talks with the US this weekend. North Korean leader Kim Jong-un and US President Donald Trump have already held two summits on the denuclearisation issue but have yet to make any concrete progress.

South Korea says the North Korean missile flew about 450km. Photo: AP alt=South Korea says the North Korean missile flew about 450km. Photo: AP

Zhao Tong, a fellow at the Carnegie-Tsinghua Centre for Global Policy in Beijing, said the purpose of the missile launch was "not to jeopardise the negotiations but to show off North Korea's military achievements" and raise the pressure on the US ahead of the talks.

"North Korea is sending the message that high-handed sanctions will not stop it from developing its nuclear capacity and that a more realistic way out is [for the US] to green light it," he said.

However, the fact that Kim was not present at the launch " KCNA said he sent his "warm congratulations" after the event " could suggest he did not want to upset Washington or Beijing too much, Zhao said.

There has been speculation that Kim might visit China on Sunday to mark the 70th anniversary of the establishment of diplomatic relations between the two countries.

But when asked about it at a press conference last week, Chinese foreign ministry spokesman Geng Shuang declined to confirm such a trip was on the cards, saying only that the two nations "maintained the tradition of friendly interaction".

The missile launch came just hours after Pyongyang announced it would resume nuclear talks with the US this weekend. Photo: Reuters alt=The missile launch came just hours after Pyongyang announced it would resume nuclear talks with the US this weekend. Photo: Reuters

Zhao said it was possible that the missile launch was an attempt by Pyongyang to show solidarity with China as it continued to fight a punishing trade war with the US.

"North Korea could be thinking that as the US increasingly sees China as a major geopolitical rival, if there is something it can do to distract the US, even in a provocative way, it will win more support from Beijing," he said.

Cheng Xiaohe, an associate professor at Renmin University in Beijing, said China might also be looking to establish common ground with North Korea ahead of its upcoming trade talks with the US in Washington.

"Any positive outcome from the North Korea-US negotiations would have a certain affirmative impact on US-China relations and vice versa," he said.

Chinese Vice-Premier Liu He is set to travel to Washington for the 13th round of top-level talks next week.

This article originally appeared in the South China Morning Post (SCMP), the most authoritative voice reporting on China and Asia for more than a century. For more SCMP stories, please explore the SCMP app or visit the SCMP's Facebook and Twitter pages. Copyright © 2019 South China Morning Post Publishers Ltd. All rights reserved.

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