- Video report by ITV News Washington Correspondent Robert Moore
Donald Trump says the US has not been told North Korea is threatening to cancel his planned summit with Kim Jong-un next month.
"We will see what happens," Mr Trump said when asked about the summit during a meeting with the president of Uzbekistan at the White House.
North Korea threatened to scrap the historic summit next month between the two leaders, saying it has no interest in a "one-sided" affair where the North would have to abandon its nuclear weapons and get nothing in return.
Speaking on Wednesday, the US president said the White House had not been notified about the threat to cancel the summit, planned for June 12 in Singapore. Mr Trump said he will still insist on the North's denuclearisation.
He added: "We haven't seen anything. We haven't heard anything. We will see what happens."
The warning from North Korea's first vice foreign minister came after the country abruptly cancelled a high-level meeting with South Korea to protest against US-South Korean military exercises that the North has long claimed are an invasion rehearsal.
Behind the scenes, White House aides tried to soothe South Korean frustrations over the cancelled meeting with the North as they continue to plan for the summit.
US officials compared the threat to Mr Trump's own warning that he might walk away from the summit if he determines Mr Kim is not serious about abandoning his nuclear programme, saying it did not appear to be serious.
The direction from the Oval Office to White House aides and other US national security agencies Wednesday was to downplay the North Korean threats and not "take the bait" by overreacting to the provocation, a senior US official said.
National Security Adviser John Bolton told Fox News Radio: "We are trying to be both optimistic and realistic at the same time."
Mr Bolton was criticised by the North for saying that the US is seeking to seek an outcome similar to Libya's unilateral nuclear disarmament.
North Korean first vice foreign minister Kim Kye Gwan said in a statement on state media: "We are no longer interested in a negotiation that will be all about driving us into a corner and making a one-sided demand for us to give up our nukes and this would force us to reconsider whether we would accept the North Korea-US summit meeting."
Secretary of State Mike Pompeo has met with the North Korean leader twice to lay the groundwork for the summit, and reported that Mr Kim had agreed to place his nuclear arsenal on the negotiating table.