Mr Kim issued the government order on Thursday during an ongoing ruling party meeting in Pyongyang, the Korean Central News Agency said.
The dictator "stressed the need to get prepared for both dialogue and confrontation, especially to get fully prepared for confrontation" with the Biden administration, KCNA said.
Such preparation was necessary to "protect the dignity of our state and its interests for independent development and to reliably guarantee the peaceful environment and the security of our state", KCNA quoted Mr Kim as saying.
In 2018/19, Mr Kim held a series of summits with then-President Donald Trump to discuss his advancing nuclear arsenal. But their negotiations fell apart after Mr Trump rejected Mr Kim's calls for extensive sanctions relief in return for a partial surrender of his nuclear capability.
Mr Biden's administration has worked to formulate a new approach on North Korea's nuclear programme that it describes as "calibrated and practical".
Details of his North Korea policy have not been publicised, but US officials have suggested Mr Biden would seek a middle ground between Mr Trump's direct meetings with Mr Kim and former President Barack Obama's "strategic patience" to curb Mr Kim's nuclear programme.
Earlier this week, leaders of the Group of Seven wealthy nations issued a statement calling for the complete denuclearisation of the Korean Peninsula and "the verifiable and irreversible abandonment" of North Korea's nuclear and missile programmes.
They called on North Korea to engage and resume dialogue and respect human rights conditions.
Mr Kim did not say what specific steps North Korea would take. But some experts have said he could launch provocative missile and other weapons tests in coming months to draw US attention and boost his leverage ahead of possible new negotiations with Washington.
In an early message to the US in January, Mr Kim threatened to enlarge his nuclear arsenal and build high-tech weapons targeting the US mainland if Washington refused to abandon its hostile policy on North Korea.
In March, Mr Kim's military performed its first short-range ballistic missile tests in a year. But North Korea still maintains a moratorium on long-range missile and nuclear tests in an indication that Mr Kim still wants to keep prospects for diplomacy alive.
Mr Kim called the ruling Workers' Party's Central Committee meeting taking place this week to review efforts to rebuild his economy, which has been severely crippled by pandemic border closings, mismanagement amid the US-led sanctions, and storm damage to crops and infrastructure last year.
On Tuesday, Mr Kim opened the meeting by warning of potential food shortages, urging officials to find ways to boost agricultural production because the country's food situation "is now getting tense".
He also urged the country to brace for extended Covid-19 restrictions, suggesting North Korea would extend its border closure and other steps despite the stress on its economy.