Optimism and caution from US ahead of Moon-Kim summit

WASHINGTON - The United States on Monday struck an optimistic but tough tone over the prospect of denuclearization on the Korean Peninsula, as the summit between Republic of Korea President Moon Jae-in and top leader of the Democratic People's Republic of Korea Kim Jong-un approaches.

US Defense Secretary James Mattis said on Monday that he was optimistic that the dialogue with the DPRK will be positive.

"Right now, I think there is a lot of reasons for optimism that the negotiations will be fruitful and we'll see," Mattis said.