Pyongyang: North Korea on Friday said it would strengthen its 'nuclear deterrent' if the US maintained its 'hostile stance', on the day the Workers' Party of Korea (WPK) began its first congress in almost four decades. The Kim Jong-un regime accused the US government of being instrumental in triggering a nuclear crisis on the Korean Peninsula, according to a statement issued by the Committee for the Peaceful Reunification of Korea (CPRK). Pyongyang claimed it has the status of a nuclear power and that it has successfully developed a hydrogen bomb, EFE news reported. The statement in which Pyongyang reaffirmed its nuclear power came a few hours before the beginning of the 7th Workers' Party of Korea (WPK) congress, a rare gathering that has not taken place since 1980. During the event, delegates are expected to announce important decisions that determine the future of policies of the hermit country, especially in economic matters, while some experts have suggested that Kim could impose a generational replacement of North Korean elites. South Korea warned on Friday that during the Congress, the North Korean People's Army could carry out a mock attack on the presidential Blue House in Seoul.