This story has been updated to include additional comments from U.S. Vice President Mike Pence.

U.S. President Donald Trump on Tuesday said all parties were making “a serious effort” towards improving the situation on the Korean Peninsula, following an announcement from South Korea that the DPRK may be willing to put its nuclear weapons on the negotiating table.

But Trump also appeared partially skeptical of the news, saying on Twitter that the DPRK’s softened stance might be “false hope.”

“Possible progress being made in talks with North Korea. For the first time in many years, a serious effort is being made