Reading a statement from Mr Johnson, British Prime Minister Theresa May's spokesman told reporters: "We welcome that President Trump and Kim Jong Un have held a constructive summit, this is an important step towards the stability of a region vital to global economic growth".
The document indicates the leaders will work toward establishment of "new US-Democratic People's Rrepublic of Korea relations".
The United States and the DPRK will join their efforts to build a lasting and stable peace regime on the Korean Peninsula.
Several lawmakers expressed alarm Tuesday with President Donald Trump's plans to halt military exercises with USA ally South Korea following his historic summit with North Korea's Kim Jong Un, with some of them arguing any deal has to be ratified by Congress.
"We're not reducing anything", Trump said.
"So I think the rhetoric, I hated to do it, sometimes I felt foolish doing it, but we had no choice", the president said.
Other congressional Democrats bashed President Trump in the wake of the summit, claiming he gave up too much without getting anything from North Korea in return.
Trump's pledge to end joint exercises with South Korea without explicit concessions from North Korea to lower the military threat posed by Pyongyang took South Korean and US military officials by surprise.
But American military officials at the Pentagon or U.S. Forces-Korea say they have received no guidance on the cancellation of the exercises.
The United States and the DPRK commit to recovering POW/MIA remains, including the immediate repatriation of those already identified.
On top of that, experts say it's unlikely the North Korean dictator would allow his regime to shift in the way they sometimes do when an economy opens.
"For Hawai'i, this should assuage fears of a possible nuclear attack from North Korea".
Secretary of State Mike Pompeo tweeted that the US negotiating team "delivers for America's swagger". "The new element is that we agreed to stop our annual exercise cycle with our South Korean allies".
Early on Tuesday, just a few hours before his meeting with Kim, Trump wrote on Twitter that "meetings between staffs and representatives are going well and quickly". The South Korean military seemed similarly surprised. Without the menace of a nuclearized and isolated North Korea next door, South Korea will be able to move away from the security arrangement it has with Washington to a more economically-oriented arrangement with Beijing.
US forces in South Korea said it has "received no updated guidance on the execution or cessation of training exercises" and will continue to coordinate with South Korean partners and maintain the current posture until it receives an updated guidance from the Department of Defense or the Indo-Pacific Command.
Following the Singapore summit, wherein Trump castigated the exercises as "provocative", no party has effectively distinguished the difference between what constitutes "readiness training and training exchanges" and what constitutes "military exercises". The senator added that because of Trump's comments referring to the end of the exercises, "that's why I said there needs to be some clarification".