Seoul: North Korea said on Wednesday its ruling Workers' Party would hold a congress from May 6, ending its silence on the date of the first such conference in 36 years, as South Korea said another North Korean nuclear test appeared imminent.
North Korean leader Kim Jong Un is expected to use the congress to cement his leadership and to formally adopt his policy, known as "byongjin", to push simultaneously for economic development and nuclear weapons capability.
North Korea's last party congress was in 1980, before Kim was born. Kim, the third member of his family to lead the country, is believed to be 33.
Byongjin follows Kim's father's Songun, or "military first", policy and his grandfather's Juche, the North's home-grown founding ideology that combines Marxism and extreme nationalism.
The party congress, first announced in October, will be closely watched for any new policies and for how the country will present its pursuit of nuclear-weapon capability. North Korea's drive to develop a nuclear capability has intensified since January, when it conducted its fourth nuclear test and followed that with a string of tests of missiles that could deliver such a weapon.
South Korea, and others nervously watching the North's defiance of UN resolutions aimed at curbing its nuclear and ballistic missile technologies, expect another test within days.
"Considering the state of readiness at the nuclear test site, it's our view that a nuclear test can happen at any time," South Korean Unification Ministry spokesman Jeong Joon-hee told a briefing on Wednesday.
South Korea's military said this week Kim's go-ahead was all that was needed for a new test. North Korea said this week it needed a "powerful nuclear deterrence" to counter US hostility and threats.
Jeong said South Korea expected the North's party congress to last four or five days.
The last Workers' Party congress was held under the rule of Kim's grandfather, Kim Il Sung, the state founder. Kim Jong Un's father, Kim Jong Il, who died in December 2011, never held a party congress.
The US State Department warned on Tuesday it would consider "other" options if the North continued nuclear testing and ballistic missile launches. It declined to elaborate.
US President Barack Obama said in an interview aired on Tuesday that there "was no easy solution" to the North Korean threat and while the United States "could destroy North Korea with our arsenals", there would not only be humanitarian costs but also potential impact on South Korea.
South Korean President Park Geun-hye has joined Obama and Japanese Prime Minister Shinzo Abe in vowing to take more steps to punish the North if it continued to defy UN sanctions and conducted more "provocative" activities.
Park said on Tuesday the effectiveness of existing sanctions could be boosted by "closing loopholes" and said the North may be "quickening its own collapse" by defying international warnings.
The North may be readying to launch an intermediate-range ballistic missile after a failed attempt this month, South Korea's Yonhap news agency reported on Tuesday.