The U.S. Congressional Research Service(CRS) reportedly says shutting down North Korea's Yongbyon nuclear facilities alone will not be enough to incapacitate the regime’s nuclear program. 

According to Radio Free Asia on Wednesday, the CRS gave the assessment in a three-page report released after the collapse of the second summit between the North and the U.S.

The report said U.S. President Donald Trump and North Korean leader Kim Jong-un appear not to have reached an agreement on what denuclearization means. 

The report also pointed out the Hanoi summit could have broken down over issues such as reporting and verifying nuclear facilities in the North.