China has always been accused of lax enforcement of United Nations sanctions on North Korea, and US President Donald Trump complained earlier this year that trade between the two countries surged in the first quarter.
North Korea imports mostly gasoline and diesel fuel from China which are vital to the country's agriculture, transportation and military sectors, according to the EIA.
His comments come after the UN Security Council unanimously adopted a US-draft resolution imposing new sanctions on North Korea.
As for energy, it caps Pyongyang's imports of crude oil at the level of the last 12 months, and it limits the import of refined petroleum products to 2 million barrels a year. Natural gas condensates and liquids are also included among the items North Korea is restricted from importing in excess of United Nations guidelines.
To shoot down a ballistic missile from North Korea would require a new generation of interceptor, the Block II, which is still in development.
"Given this situation, we need to watch further (to gauge North Korea's intention)".
North Korea's leader Kim Jong-un ordered the production of more rocket warheads and engines, shortly after the United States suggested that its threats of military action and sanctions were having an impact on Pyongyang's behavior.
Chinese foreign ministry spokesman Geng Shuang told reporters that Beijing "approves further reactions and necessary measures by the UN Security Council" in response to the nuclear test.
The Trump administration warned Tuesday that the US will punish companies in China and Russian Federation that don't comply with restrictions in the new global sanctions on North Korea.
North Korea's Foreign Ministry said in a statement published on state media that if the USA "does rig up the illegal and unlawful 'resolution, '" it would respond in kind.
While China is the patron of North Korea, Russia is the other important trading partner that also hosts a large number of expatriate workers from that country.
China's official Xinhua news agency said in a commentary that the Trump administration was making a mistake by rejecting diplomatic engagement with North Korea.
North Korea is threatening war, again, should the United Nations pass the harshest sanctions yet to punish the country for its latest nuclear test.
"The one factor working in favor of these sanctions being implemented is that the Chinese and Russians have to be fearful that the US will impose its own sanctions on Chinese and Russian companies", he said.
North Korea says it will make the United States pay a heavy price if a proposal Washington is backing to impose the toughest sanctions ever on Pyongyang is approved by the U.N. Security Council this week. The ship then docked in Vladivostok, Russia, before finally going to China to presumably unload its cargo.
"But to achieve such a solution, the pressure on North Korea must be increased". China, though, has been reluctant to shut off its oil pipeline to North Korea or undertake any measures which could lead to a failed state on its border.