Home North Korean leader Kim Jong-un (L) and U.S. President Donald Trump (R) sign a document to bring peace and stability to the Koreas during their historic U.S.-DPRK summit at the Capella Hotel on Sentosa island on June 12, 2018 in Singapore.<br> (Photo by Kevin Lim/The Strait Times/Handout/Getty Images) North Korean leader Kim Jong-un (L) and U.S. President Donald Trump (R) sign a document to bring peace and stability to the Koreas during their historic U.S.-DPRK summit at the Capella Hotel on Sentosa island on June 12, 2018 in Singapore.<br> (Photo by Kevin Lim/The Strait Times/Handout/Getty Images)

North Korean leader Kim Jong-un (L) and U.S. President Donald Trump (R) sign a document to bring peace and stability to the Koreas during their historic U.S.-DPRK summit at the Capella Hotel on Sentosa island on June 12, 2018 in Singapore.
(Photo by Kevin Lim/The Strait Times/Handout/Getty Images)

North Korean leader Kim Jong-un (L) poses for photos with U.S. President Donald Trump (R) during their historic U.S.-DPRK summit in Singapore on Tuesday, June 12, 2018.<br>(Photo by Handout/Getty Images)
U.S. President Donald Trump (R) displays a document signed by North Korean leader Kim Jong-un to bring peace and stability to the Koreas during their historic U.S.-DPRK summit at the Capella Hotel on Sentosa island on June 12, 2018 in Singapore.<br> (Photo by Kevin Lim/The Strait Times/Handout/Getty Images)