North Korean leader Kim Jong Un criticized party officials for “serious deviations” of failing to keep up with reality at a major ideological conference in Pyongyang on Saturday, according to DPRK state media, while also praising officials for helping the country overcome “unprecedented challenges and ordeals.”

Kim did not specify the nature of these deviations or challenges in an opening speech at the 2nd Conference of Secretaries of Primary Committees of the country’s Workers’ Party of Korea (WPK), while urging the officials to review and learn from their past mistakes, the Korean Central News Agency reported on Sunday.