The United States is hopeful that talks between the leaders of North and South Korea will make progress on achieving peace and prosperity, the White House has said in a statement.
North Korean leader Kim Jong-un and South Korean President Moon Jae-in have pledged to work for the "complete denuclearisation of the Korean peninsula."
The White House said it looks forward to continuing discussions with South Korea in preparation for the planned meeting of President Donald Trump and Mr Kim in the coming weeks.
Just months ago, Mr Trump and Mr Kim were trading threats and insults as the North made rapid advances in pursuit of nuclear-armed missiles capable of hitting the United States.
He said this morning in a tweet that good things are happening after a "furious year of missile launches and Nuclear testing".
After a furious year of missile launches and Nuclear testing, a historic meeting between North and South Korea is now taking place. Good things are happening, but only time will tell!— Donald J. Trump (@realDonaldTrump) April 27, 2018
Japanese Prime Minister Shinzo Abe welcomed the summit as a positive step and he strongly expected Pyongyang to take concrete steps towards to carry out its promises.
Japan would stay in close contact with the US and South Korea over North Korea, Mr Abe said, adding that Japan was "absolutely not" being left out of the denuclearisation process.
The North and South Korean leaders said they would pursue trilateral meetings with the United States and that meetings involving the two Koreas, the United States and China were also possible
Russia hailed the historic summit as very positive news and said President Vladimir Putin had long advocated direct talks between the two countries.
When asked about the prospect of US President Donald Trump also meeting the North Korean leader, Kremlin spokesman Dmitry Peskov told reporters on a conference call that Moscow welcomed any steps that would ease tensions on the Korean Peninsula
China also welcomed the joint statement by North and South Korea and hoped all parties can maintain the momentum for dialogue and can jointly promote the political resolution process for the Korean peninsula issue, the Foreign Ministry said in a statement.
China is willing to keep playing a pro-active role in this regard, it added.
NATO chief Jens Stoltenberg hailed the historic summit as "encouraging", but warned that more challenges lay ahead.
"This is a first step, it is encouraging, but we have to realise there is still a lot of hard work that lies ahead of us," Mr Stoltenberg said at a meeting of NATO foreign ministers in Brussels.