Washington. Seoul: US President Donald Trump says the US military is "ready if necessary" to respond to "foolish or reckless acts" by North Korea.
Trump also says he's been in touch with South Korea and Japan, and that both allies are willing to bear much of the financial burden "if such an unfortunate situation is forced upon us".
Trump on Thursday announced he has called off a planned June 12 summit with North Korea's leader, Kim Jong-un, citing recent hostile statements by Kim's government.
North Korea overnight threatened nuclear confrontation with the US and called Vice-President Mike Pence a "political dummy".
Trump says hopefully "positive things" will take place with respect to North Korea's future. But, he adds, "If they don't we are more ready than we have ever been before."
South Korean President Moon Jae-in convened emergency talks with his top security aides late on Thursday after Trump cancelled his planned summit with Kim, Seoul's Yonhap news agency reported.
Moon summoned his chief of staff, top security advisor, intelligence chief, unification minister and others to the presidential Blue House at 1130 pm (1430 GMT), his press secretary Yoon Young-chan said in a message to reporters, according to Yonhap.
Officials in Seoul "are trying to figure out what President Trump's intention is and the exact meaning of it", Yonhap reported, quoting presidential spokesman Kim Eui-kyeom, following Trump's decision to pull out of the high-stakes meeting agreed for June 12 in Singapore.
UN Secretary-General Antonio Guterres on Thursday said he was "deeply concerned" as US President Donald Trump cancelled a widely anticipated nuclear summit next month with North Korean leader Kim Jong-un.
"I am deeply concerned by the cancellation of the planned meeting in Singapore between the President of the United States and the leader of the Democratic Peoples Republic of Korea, and I urge the parties to continue their dialogue to find a path to a peaceful and verifiable denuclearisation of the Korean peninsula," Guterres said as he presented a new UN disarmament agenda in Geneva.
The summit between President Donald Trump and North Korean leader Kim Jong-un was scrapped because a "successful outcome" did not seem possible, Secretary of State Mike Pompeo said.
"I don't believe in that sense that we're in a position to believe that there could be a successful outcome. Over the past many days, we have received no response to our inquiries from them," Pompeo told US lawmakers.
Earlier in the day, Trump called off his planned June 12 summit meeting with North Korean leader Kim in a letter released by the White House.
"I was very much looking forward to being there with you," Trump said in the letter. "Sadly, based on the tremendous anger and open hostility displayed in your most recent statement, I feel it is inappropriate, at this time, to have this long-planned meeting."
Timeline charting the recent developments in North Korean diplomacy as Donald Trump says his planned June 12 summit with Kim Jong Un will no take place pic.twitter.com/Ik30nLCbEt— AFP news agency (@AFP) May 24, 2018
Below is the full text of the letter
Dear Mr. Chairman:
We greatly appreciate your time, patience, and effort with respect to our recent negotiations and discussions relative to a summit long sought by both parties, which was scheduled to take place on June 12 in Singapore. We were informed that the meeting was requested by North Korea, but that to us is totally irrelevant. I was very much looking forward to being there with you. Sadly, based on the tremendous anger and open hostility displayed in your most recent statement, I feel it is inappropriate, at this time, to have this long-planned meeting. Therefore, please let this letter serve to represent that the Singapore summit, for the good of both parties, but to the detriment of the world, will not take place. You talk about your nuclear capabilities, but ours are so massive and powerful that I pray to God they will never have to be used.
I felt a wonderful dialogue was building up between you and me, and ultimately, it is only the dialogue that matters. Some day, I look very much forward to meeting you. In the meantime, I want to thank you for the release of the hostages who are now home with their families. That was a beautiful gesture and was very much appreciated.
If you change your mind having to do with this most important summit, please do not hesitate to call me or write. The world, and North Korea in particular, has lost a great opportunity for latest peace and great prosperity and wealth. This missed opportunity is a truly sad moment in history.
Donald J. Trump
President of the United States of America