North Korea's state-run media say the ruling Workers' Party congress opened on Tuesday, the first such gathering in five years and just weeks before US President-elect Joe Biden takes office.
North Korean leader Kim Jong Un admitted there had been an economic slump, saying a five-year economic plan that was due to finish last year had failed to meet its goals in almost every sector.
The party's newspaper, Rodong Sinmun, says he made the remarks when he kicked off the congress on Tuesday.
When it comes to diplomacy, he said he will suggest "strategic and tactical policies" for "the cause of national reunification, promoting external relations and strengthening the work of the party."
It's likely a new five-year economic plan will be unveiled during the gathering, potentially taking into consideration the negative impact of UN Security Council sanctions and border closures due to the coronavirus pandemic.
The congress is expected to last several days.
Attention is focused on what policies the North will lay out for its nuclear and missile programs before Biden takes office.
The US research group 38 North says satellite images taken on December 31 indicate Pyongyang is preparing a military parade to coincide with the congress.
The group says one image shows more than 400 large vehicles parked on the parade ground and troop formations training along the practice route.