U.S. President Donald Trump said on Tuesday North Korean leader Kim Jong Un had made an "unwavering commitment" to the complete denuclearisation of the Korean peninsula but sanctions against North Korea would remain in effect.

Trump, speaking after his historic summit meeting with Kim in Singapore, said both leaders were "prepared to start a new history and write a new chapter between our nations".

"He reaffirmed his unwavering commitment to the complete denuclearisation of the Korean peninsula," Trump told a news conference.

Trump said Kim had "an opportunity like no other", and that Kim had said a North Korean missile testing site "is going to be destroyed very soon".

Trump also said he would be "stopping the war games", apparently referring to unspecified military exercises.

Trump also said he and Kim had discussed human rights briefly.