Prime Minister Lee Nak-yon says Seoul and Washington have yet to conclude what motives are behind Pyongyang's actions following the unsuccessful second summit between North Korea and the U.S. 

Lee was speaking at a parliamentary interpellation session on Thursday, where he faced questions regarding the possibility that the North may resume its missile and nuclear activities, a speculation further boosted by its threat to suspend talks with the U.S.

The prime minister said the two allies are closely monitoring and analyzing the North’s moves. 

He said complete denuclearization is an agreed goal among the two Koreas and the U.S. although the North and the U.S. have not reached consensus yet on what the final phase of denuclearization will look like. 

Noting South Korea and the U.S. share strategic goals on the issue, the prime minister said now is the time for the North to show its will to denuclearize and hoped the regime will use wise judgment.