North Korean leader Kim Jong-un’s influential sister warned the US against actions that could make it “lose sleep”, state media reported on March 16, as top Biden administration officials began a visit to key allies Tokyo and Seoul.

Pentagon chief Lloyd Austin and US Secretary of State Antony Blinken arrived in Japan on March 15 on their first overseas trip, aimed at rallying military alliances to cement a united front against the nuclear-armed North Korea.

The statement by Kim Yo-jong, a key adviser to her brother, was Pyongyang’s first explicit reference to the new president in Washington, more than four months after Joe Biden was elected to replace Donald Trump – although it still did not mention the Democrat by name.

The US and South Korea began joint military exercises last week and Pyongyang’s official Rodong Sinmun newspaper carried a statement from her offering “a word of advice to the new administration of the United States that is struggling to spread the smell of gunpowder on our land”.

“If you wish to sleep well for the next four years, it would be better not to create work from the start that will make you lose sleep,” she said.

Trump’s unorthodox approach to foreign policy saw him trade insults and threats of war with Kim Jong-un before an extraordinary diplomatic bromance that saw a series of headline-grabbing meetings.

But ultimately no progress was made towards Washington’s declared aim of denuclearising North Korea, which is under multiple international sanctions for its banned weapons programmes.

‘March of war’

North Korea has isolated itself further, imposing a strict border closure to protect itself against the coronavirus pandemic.

Shortly before Biden’s January inauguration, leader Kim decried the US as his country’s “foremost principal enemy” and Pyongyang unveiled a new submarine-launched ballistic missile at a military parade.

The talks process was brokered by South Korea’s President Moon Jae-in but relations between Seoul and Pyongyang have been in deep freeze since Kim and Trump’s summit in Hanoi collapsed in February 2019.

Kim Yo-jong is a trusted adviser to her brother and was a key voice when inter-Korean tensions mounted last year, culminating in the North blowing up a liaison office on its side of the border.

Shin Beom-chul, a researcher at the Korea Research Institute for National Strategy, pointed out that her announcements have previously represented incremental steps by Pyongyang.

He said: “North Korea has judged that the US will not offer enough concessions and so has released this statement ahead of Blinken and Austin’s visit to Seoul.”