Tensions rose after North Korea's test this month of an intercontinental ballistic missile that could reach the U.S. mainland.
The Chinese General Administration of Customs denied the insinuation, saying that bilateral trade had grown by 10.5 percent in the first half of 2017 and that the growth was prompted mainly by Chinese export products to the DPRK not included in the sanction list, such as textiles.
He said imports from North Korea have fallen for the past four months and all coal imports were made in the first two months of the year, before China suspended coal purchases from Pyongyang.
While China's imports from North Korea dropped 13.2 percent to $880m in the period from January to June, exports to North Korea rose 29.1 percent to $1.67bn, he said.
"Simple accumulated data can not be used as evidence to question China's severe attitude in carrying out UN Security Council resolutions", Huang told a news briefing.
China's imports of the steelmaking material from all countries jumped 16% from a year earlier in June and rose 9.4% for the first half, customs data showed, as a lasting property boom has spurred demand from the construction sector. He referred to "tough pressures" that China faces in its relationship with North Korea.More news: Leonardo Bonucci on verge of shock AC Milan transfer
But the Trump administration's patience grew even thinner last week after Pyongyang conducted its first successful test of an intercontinental ballistic missile believed to be capable of striking the U.S.
However Chinese officials have previously expressed their disdain for North Korea's provocative actions.
Beijing was quick to pour cold water on the suggestion that the overall rise in trade suggested it was not complying with U.N. Security Council resolutions created to punish Pyongyang for its nuclear tests and missile launches. Chinese officials say the February suspension of imports of North Korean coal for the rest of this year was part of efforts to enforce those sanctions.
The data on the customs agency's website didn't break out iron-ore imports from North Korea in the first half.
"Trade between China and North Korea grew nearly 40 per cent in the first quarter".
China insists none of its current trade with Pyongyang is in violation of worldwide sanctions. Despite that track record, the Trump White House displayed an initial optimism, presenting North Korea as an easily solvable problem with the help of Chinese President Xi Jinping, with whom Trump had a friendly summit back in April.