The U.S. military conducted another show of force to North Korea on Wednesday as long-range B-1 bombers flew a nighttime mission over the Sea of Japan accompanied by Japanese and South Korean fighter aircraft.
Mr Ri also said the North's nuclear programme is a "precious fruition of the Korean people's bloody struggle for defending the destiny and sovereignty of the country from the protracted nuclear threat of the United States imperialists and a treasured sword of justice".
The North Korean authorities were reported to have told one of the delegates that they were preparing the next test launch with a new intercontinental ballistic missile capable of reaching the west coast of the US. Pyongyang has historically conducted tests on noteworthy anniversaries and holidays such as a missile test on July 4 for America's Independence Day.
Trump has engaged in an escalating war of words with North Korean dictator Kim Jong-Un amid rising tensions between the two countries. She described herself as a moderate Republican but voiced anxiety about how North Korea might respond to Trump's tough talk and tweets.
The B-1B Lancers, which flew from Andersen Air Force Base in Guam, were joined by South Korean fighter jets after entering the Korean Air Defense Identification Zone about 8:50 p.m. Tuesday, the South Korean military said.
"The briefing and discussion focused on a range of options to respond to any form of North Korean aggression or, if necessary, to prevent North Korea from threatening the United States and its allies with nuclear weapons", the White House said in a statement on the meeting.
Australia's foreign and defense ministers visited the heavily fortified inter-Korean border Thursday and emphasized the need to inflict "maximum diplomatic pressure" to rein in North Korea's nuclear ambition. Last month he got China to agree to new U.N. Security Council sanctions on North Korea.
U.S. officials have voiced their concern that Kim Jong-un's nation could launch cyber attacks on American infrastructure.
Ri has previously called Trump "President Evil" and his comments are likely to fuel an escalating war of words between the United States president and North Korean leader Kim Jong Un. Some military experts believe that power supply problems make it hard for North Korea to turn on its air defense radars for 24 hours a day and also that the systems might struggle to effectively track advanced warplanes such as B-1Bs, which have low radar-cross sections. He also boasted that his nation has nearly achieved a "balance of force" with the U.S.
The US has repeatedly ruled out negotiations with North Korea.
"Our country has been unsuccessfully dealing with North Korea for 25 years, giving billions of dollars & getting nothing".