Prime Minister Shinzo Abe said Wednesday that Tokyo will work closely with Washington to tackle challenges related to North Korea in the run-up to the second summit between U.S. President Donald Trump and North Korean leader Kim Jong Un later this month.

"It may be difficult to hold (direct) summit talks (with Trump) due to tight schedules, but through a phone conversation, we will closely coordinate our policies over the issues of nuclear weapons, missiles and abductions, the latter of which is the most important for Japan," Abe told an Upper House committee, referring to past abductions of Japanese nationals by Pyongyang.

Trump took up the matter during his first summit with Kim in Singapore in June at Abe's request. The prime minister has voiced his readiness to meet with the North Korean leader in person in an attempt to achieve a breakthrough on the issue.