North Korea will “never” return to dialogue with the U.S. if Washington doesn’t give up challenging Pyongyang’s “sovereignty” over issues like its recent satellite launch, the North Korean leader’s sister Kim Yo Jong warned Thursday.

“The sovereignty of an independent state can never be an agenda item for negotiations, and therefore, the DPRK will never sit face to face with the U.S. for that purpose,” she said in a statement released by the Korean Central News Agency (KCNA), calling out diplomats who “asked the DPRK to fix the time and agenda for resuming the DPRK-U.S. dialogue.”