Kim Jong Un in China for talks

North Korean leader Kim Jong Un began a four-day trip to China on Tuesday, meeting with his only major ally ahead of a possible second summit with U.S. President Donald Trump. The North Korean Central News Agency said Kim traveled with his wife, Ri Sol Ju, and other leading officials at the invitation of Chinese President Xi Jinping. This trip is Kim’s fourth meeting with Xi.

The United States and North Korea have yet to confirm the date and location of a second summit to discuss North Korea’s denuclearization. During his New Year’s Day speech last week, Kim expressed commitment to ending his country’s nuclear program but warned he would seek an alternative if the United States persisted with sanctions and pressure on North Korea.

Chinese Foreign Ministry spokesman Lu Kang did not release any information about the meeting with Xi but said China remains committed to the denuclearization efforts. “We always believe that, as key parties to the Korean Peninsula issue, it’s important for the two sides to maintain contact, and we always support their dialogue to achieve positive outcomes,” he said.