North Korean leader Kim Jong Un’s powerful sister mocked South Korean President Yoon Suk-yeol in a New Year’s message on Wednesday, stating that his “stupid and honest” inter-Korean policy focused on deterrence has provided Pyongyang “justification” to develop nuclear weapons.

The statement by Kim Yo Jong unfavorably compared Yoon to his “smart” progressive predecessor Moon Jae-in, whom she said built up the ROK military even while “pretending” to care about peace, in what experts called an attempt to fan the flames of political division in South Korea.