North Korean leader Kim Jong Un emphasised the need to take "offensive" measures to ensure security at a major party conference deemed by observers as a political show to keep the world guessing about his next move.
The meeting came as the United States warned the North against causing any provocation, while United Nations Security Council (UNSC) members were due to gather to discuss a proposal backed by China and Russia to lift some sanctions against the North.
The unusually long plenary meeting of North Korea's Workers' Party - the highest form of policy discussion - was due to enter its third day yesterday, according to state media reports.
The Korean Central News Agency (KCNA) said Mr Kim on Sunday stressed the need to take "positive and offensive measures for fully ensuring the sovereignty and security of the country as required by the present situation".
But there were no details on what the measures could be.
The state-owned Rodong Sinmun, meanwhile, praised Mr Kim's "exceptional military aptitude" and "cumulative unique achievements" as the supreme commander of the country's army, as it marked the eighth anniversary of his leadership.
The party conference comes ahead of a year-end deadline imposed by North Korea for resuming denuclearisation talks with the US that have stalled for months, and just before Mr Kim was due to make his annual New Year's Day speech outlining his vision and key policies for 2020.
Concern has been growing that Mr Kim would ditch negotiations with the US and resume the testing of long-range missiles and nuclear tests, as he sought to embark on the "new path" as threatened earlier.
US National Security Adviser Robert O'Brien said on Sunday that Washington will be "extraordinarily disappointed" if Pyongyang tests a long-range missile, and it will take action.
"We have a lot of tools in our toolkit, and additional pressure can be brought to bear on the North Koreans," he said in an ABC interview.
The US Air Force has also strengthened its surveillance of the Korean peninsula in recent weeks, most recently flying a surveillance plane over the region yesterday.
Meanwhile, UNSC members were due to meet yesterday for a second round of talks over a draft submitted by China and Russia - both friendly towards North Korea - to lift some sanctions on the regime.
Pyongyang has been sanctioned by the UN since 2006 over its nuclear and missile programme.
While they supported the tightening of sanctions before, China and Russia have voiced hope that lifting some sanctions could help break the nuclear deadlock and encourage talks to resume between the US and North Korea.
Dr Cheong Seong-chang of Sejong Institute, a think-tank, pointed out that it has been about 30 years since North Korea convened such a long party conference, which signalled the severity of the situation faced by the regime.
Previous meetings lasted only one or two days.
Dr Cheong noted that North Korea's economy has been affected by the sanctions-triggered repatriation of its people sent overseas to work to bring back much-needed foreign currency, and there is growing concern about this.
"North Korea's isolation has deepened and red lights are flashing on its economy," he said.
"Kim Jong Un must offer his party and government officials a strategy to deal with the harsh trials and challenges ahead."
Professor Leif-Eric Easley of Ewha Womans University, however, called the party conference "political theatre for both domestic and international consumption".
"Kim wants to appear strategic rather than tactical, proactive rather than reactive, and calculating rather than capricious," he said.
He noted that the "current international obsession over Kim's next move is exactly what he wants", but the world should remain united to "disabuse the Kim regime of the notion that it can win economic benefits and weaken US alliances while holding on to its nuclear weapons, missiles and aggressive military tests and exercises".
