South Korea's presidential office says it believes U.S. President Donald Trump's remark on the possibility of more meetings with North Korean leader Kim Jong-un was not made to lower expectations on next week's summit meeting in Vietnam.

In a regular briefing Thursday, presidential spokesman Kim Eui-kyeom said President Trump’s comments imply that step-by-step follow-up talks may take place, but added this is a subjective opinion and interpretation by the top office.

Kim said that denuclearization can't be achieved all at once but will take a long time and must be done in stages.

He said that he believes President Trump was simply explaining the situation regarding ongoing talks and the stage of dialogue.

The spokesman said that when President Moon Jae-in and President Trump have the opportunity to meet after the North Korea-U.S. summit, it will be a chance for President Moon to share his thoughts and ideas concerning concrete and substantive follow-up measures to the summit. 

Regarding media reports saying that U.S. National Security Adviser John Bolton will visit Seoul this weekend, the spokesman said it is not something the Seoul government can verify.