Kim Yo-jong was quoted in the official Rodong Sinmun newspaper as saying: "A word of advice to the new administration of the United States that is struggling to spread the smell of gunpowder on our land from across the ocean". "War drill and hostility can never go with dialogue and cooperation".
Biden's predecessor Donald Trump engaged in unprecedented summit diplomacy with Kim Jong Un.
Under Trump, the world saw an unusual bromance between the leaders of the world's oldest democracy and one of the most notorious dictatorships after trading threats of war. The former USA president met North Korea's leader three times in 2018 and 2019 in the hopes of convincing the Asian nation to give up its pursuit of nuclear weapons.
It is to be noted that shortly before Biden's inauguration in January 2021, Kim announced the USA as his country's "foremost principal enemy". Still, despite three in-person meetings and the slew of "beautiful letters" that Donald Trump received from the North Korean leader, the "historic" talks led nowhere - and ultimately left allies South Korea and Japan wondering whether they could count on United States protection as Pyongyang repeatedly threatened them in word and deed. He had upended diplomatic norms by meeting not once, but three times, with North Korean leader Kim Jong Un.
North Korea's official media, which during the USA presidential campaign called Biden an "imbecile bereft of elementary quality as a human being", has yet to mention him by name since his election victory.
But the exercise was limited to computer simulations because of the coronavirus risk, as well as the ongoing efforts to engage with the North.
The Biden administration is still conducting a review of the Trump administration's North Korea policy, which could be announced "in the coming weeks", according to a senior State Department official.
The timing of Kim's comments seems created to ensure that North Korea will be at the top of Blinken and Austin's agenda when they land in Seoul, said Ramon Pacheco Pardo, a Korea expert at King's College London.
South Korea and the US kicked off their springtime combined military drills early last week involving a "minimum level of troops" given the coronavirus situation.
Blinken and Austin are expected to finalize tentative deals on financing U.S. troops stationed in South Korea, as well as a similar deal with Japan.
Leader Kim Jong Un had three high-profile summit meetings with former president Donald Trump and exchanged a series of letters, but North Korea later ended talks and said it would not engage further unless the USA dropped its hostile policies. And for the first time ever, there was also an official message to the Biden administration, who recently reached out to Pyeongyang without receiving a direct response.
Their first official overseas visits are meant to restore what Mr Biden hopes will be a calming and even-keeled approach to ties with Tokyo and Seoul after four years of transactional and often temperamental relations under the previous president, Donald Trump.