A statement from the White House says Trump and Moon "affirmed that North Korea poses a grave and growing direct threat to the United States, South Korea, and Japan, as well as to most countries around the world".
North Korea said the latest sanctions infringed its sovereignty and it was ready to give Washington a "severe lesson" with its strategic nuclear force in response to any US military action. But it was put off because of reasons on the USA side.
Despite the strong posturing, North Korea has found itself increasingly isolated since it conducted two intercontinental ballistic missile (ICMB) tests last month. "So it is all about how we see their attitude towards approaching a dialogue with us".
Stung by the latest round of United Nations sanctions, North Korea is likely on the lookout to expand its illicit trade outlets.
Foreign Minister Taro Kono and U.S. Secretary of State Rex Tillerson agreed on Monday that their countries will hold a so-called two-plus-two meeting of the foreign and defense ministers in Washington on August 17. The American and Japanese diplomats held another three-way session with Australia. They said they were committed to providing help in implementing them.
North Korea has previously used misogynistic slurs to describe former South Korean President Park Geun-hye, the country's first woman leader.
The administration says the resolution could cost the regime $1 billion a year, although sanctions experts say that depends largely on how well they are implemented - especially by China, whose track record on enforcing punitive measures on North Korea is poor.
Yet already, there are signs that nations with the strongest ties to North Korea may fall short of the stringent enforcement that Trump and others seek.
The UN Security Council unanimously imposed new sanctions on North Korea on Saturday aimed at pressuring Pyongyang to end its nuclear programme.
Still, the key concern is over China, the North's economic lifeline and biggest trading partner.
But Tillerson says it's not as simple as North Korea stopping launches for a few days or weeks. Tillerson says he and the South Korean diplomat plan to discuss the sanctions during their meeting, along with next steps to pressure the North. "If you really start to go down that path, I'm not sure how far the Chinese will go down with you".
Pyongyang props up its nuclear program with income from the sale of various illegal goods, including weaponry, synthetic drugs, counterfeit currency and nuclear technology.
"We will, under no circumstances, put the nukes and ballistic rockets" up for negotiation, Ri said in prepared remarks, adding the entire U.S.is within range of its missiles.
"We hope again that this ultimately will result in North Korea coming to a conclusion to choose a different pathway, and when the conditions are right that we can sit and have a dialogue around the future of North Korea so that they feel secure and prosper economically", added Tillerson, the Post reported.
Tillerson conceded there would likely be a lag period before the sanctions "actually have a practical bite on their revenues".
All 10 countries in ASEAN have diplomatic relations with North Korea, including five that have embassies in Pyongyang.