The North called it a "a fatal mistake" to assume it would "tolerate" more sanctions, but it didn't exactly say what it would do in response.
North Korea gets most of its fuel from China, with some coming from Russian Federation.
The 38 North website, which monitors the rogue country's missile program, said that thermal imagery of a nuclear complex appeared to show Pyongyang had reprocessed spent fuel rods at least twice between last September and June this year. We have much to learn from confidence-building measures adopted during the Cold War to diminish risks of nuclear annihilation from needless provocation and accidental war. South Korea and the United States dispute the claim.
Moon was elected in May on a plan to engage in talks with North Korea.
South Korea's Unification Minister Cho Myoung-gyon also urged the restoration of communication hotlines between the two Koreas, cut past year after a North Korean nuclear test.
Anthony Ruggiero, a former deputy director of the US Treasury Department, said: "The message to North Korea should be, if you're here, we're here, and we're going to give these countries and these banks and companies a choice - continue to do business in the US dollar or work with North Korea".
Park's conservative government said 70 percent of the US dollars paid as wages and fees at Kaesong was channelled to the North's ruling party. It recent test of an ICBM put it one step closer to its goal of developing nuclear-armed missiles capable of reaching anywhere in the United States. The US is South Korea's second-largest trade partner, after China.
North Korea says the South abducted the 12 waitresses and the restaurant manager and has demanded their return, but the South has said the group made a decision to defect of its own free will. Cho said this matter is not included on the talks agenda.
Chinese foreign ministry spokesman Geng Shuang hit out on Tuesday against "certain people, talking about the Korean Peninsula nuclear issue, [who] have been exaggerating and giving prominence to the so-called "China responsibility theory".
"There is no military solution to the threat of a nuclear North Korea", said Markey who is the ranking Democrat on the East Asia, the Pacific, and International Cybersecurity Subcommittee.