North Korean leader Kim Jong Un has ordered preparations for a second summit with US President Donald Trump, saying he’ll “wait with patience and in good faith” to work toward a common goal, the North’s state media reported Thursday.

Despite Kim’s determination for another meeting with Trump, the two remain at odds over fundamental issues. Experts say a major sticking point is what denuclearization steps Kim should take to move forward stalled nuclear negotiations and what rewards Trump should provide to push Kim to take those measures.

The Korean Central News Agency said Kim received a letter from Trump from a North Korean envoy who met the US president in Washington last week. After meeting Kim Yong Chol, Trump said that he and Kim Jong Un will probably meet around the end of February but did not say exactly when and where the summit would take place.

Thursday’s report said Kim expressed satisfaction with his envoy’s meeting with Trump and spoke highly of the US president for “expressing his unusual determination and will for the settlement of the issue with a great interest in the second summit,” AP reported.

“We will wait with patience and in good faith and, together with the US, advance step by step toward the goal to be reached by the two countries,” Kim was quoted as saying.

Kim also “set forth tasks and orientation for making good technical preparations” for the second summit high on the agenda, according to KCNA.

Nuclear negotiations have been stuck since Kim and Trump met in Singapore last June for their first summit, which ended with Kim’s vague denuclearization pledge that his government had previously used when it called for the withdrawal of the 28,500 US troops in South Korea. A summit accord also stated that the United States and North Korea will commit to establishing new relations and join efforts to build a lasting and stable peace on the Korean Peninsula.

The strongest step Kim could promise during a second summit may be abandoning his long-range missile program targeting the US mainland. That step, if realized, would trigger a strong backlash from many in South Korea and Japan, which are within the striking distance of North Korea’s short- and medium-range missiles. In return, Kim is seeking to get UN sanctions lifted. He also wants better relations with the United States to try to revive his country’s moribund economy to pave the way for a prolonged rule by his family, experts say.

North Korea observers say Vietnam is likely to be chosen as a venue for a second summit but there has been no official confirmation.

The negotiations have replaced fears of war following a series of North Korean high-profile nuclear and missile tests in 2017 that were followed by exchanges of crude insults and threats of total destruction between Kim and Trump.

Kim has so far suspended nuclear and missile tests, dismantled North Korea’s nuclear testing site and parts of its rocket engine test facility and taken conciliatory measures, like releasing American detainees. The North now says it’s time for the US to come up with reciprocal measures.

But satellite footage indicates North Korea is still running its main nuclear complex, raising questions why it’s producing nuclear material if it is truly committed to denuclearization. US officials want North Korea to take more significant steps such as a declared accounting of its nuclear weapons program for future inspections. The North has rejected that, saying such a declaration would be like providing coordinates for US military strikes on its nuclear facilities.