The United States and North Korea are reportedly considering an exchange of liaison officers, two sources with knowledge of the discussions told CNN. The exchange is seen as an incremental step towards building formal diplomatic relations. The two high-level diplomatic sources said there would be several liaison officers sent to set up office in North Korea, led by a senior foreign service officer. News of the potential exchange comes days ahead of President Trump and North Korean leader Kim Jong Un's second summit, which is set to take place in Vietnam. The two leaders met in Singapore last year and signed a joint statement that included commitments from each country to establish relations aimed towards “peace and prosperity.” This statement left the door open to a re-establishment of formal relations sources said, adding that North Korea is expecting some significant gesture from President Trump.