(CNN) US Secretary of State Mike Pompeo said he would raise the issue of abductions as well as nuclear and missile concerns on behalf of Japan when he meets with North Korean leader Kim Jong Un in Pyongyang on Sunday.
Pompeo and Japanese Prime Minister Shinzo Abe vowed Saturday to work together as they posed for photojournalists in Tokyo before their bilateral meeting.
Pompeo said he wanted "a fully coordinated, unified view of how to proceed, which will be what is needed if we are going to be successful in denuclearizing North Korea."
Abe expressed his gratitude and said he "highly valued" the fact that Pompeo came to visit Japan right before his visit to Pyongyang. "I would like to have thorough coordination with you on our respective policies towards North Korea," he said.
Pompeo is expected to lay the groundwork for a second summit between US President Donald Trump and Kim while in Pyongyang. The trip will be Pompeo's fourth to North Korea.
Since the two leaders' meeting in Singapore in June, negotiations between the US and North Korea have stalled. Trump canceled Pompeo's planned trip to the North Korean capital in August, citing little evidence that North Korea had come through on any of its commitments to denuclearize.
Speaking to reporters en route to Japan, Pompeo said the purpose of his trip to North Korea was "to make sure we understand what each side is truly trying to achieve" and how each side was "seeking to approach" the objective of getting to the end state that was agreed to by Trump and Kim in Singapore.
Pompeo said the plan was to "develop options for both location and timing" during his trip, although he doubted they would "get it nailed" down mostly due to scheduling and logistics issues.
Pompeo would not say if he was bringing anything such as letters or gifts from Trump to Kim. "I am not bringing anything that we are prepared at this point to talk about publicly," he said.
Speaking at a rally in Wheeling, West Virginia, last weekend, Trump said that he and Kim "fell in love."
Critics have pointed out that the Singapore declaration contained no firm commitments from North Korea to dismantle its nuclear and missile programs and US officials have expressed frustration at North Korea's evasion of sanctions.
Abe has previously pressed Trump to remember the fate of Japanese citizens abducted by North Korea. A report in 2014 by the United Nations Human Rights Council concluded that hundreds of South Koreans, Japanese and other foreign nationals were kidnapped by North Korea after the end of the Korean War in 1953.