The General Administration of Customs released the June data without giving any percentage changes.
Exports of steel products fell 2.4% to 6.81 million tonnes from the previous month, according to Reuters calculations based on the data.
About 90 percent of North Korea's exports go to China, and coal has been the single-biggest export item.
Furthermore, as coal exports have reportedly fallen, shipments of iron ore have spiked.
Exports from China denominated in the yuan increased by 15% during the first six months of this year compared to the same time one year ago, while imports were up 25.7% during that same period.
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.
Huang called for an objective attitude towards this growth, however, as related UN Security Council sanctions do not ban all trade with the DPRK. Imports have fallen since March, when they declined 36.5 percent, he said.
He did not though make clear whether China believed North Korea's latest missile test last week, which the United States described as a first ICBM test, was of that type of missile.
Huang said the price fluctuation of commodities could also potentially boost the trade figure as measured by value. The surplus with the United States was China's largest since October 2015.
Washington says the exercises are needed to maintain defenses against North Korea and US officials say Beijing could face USA economic and trade pressure unless it does more to rein in North Korea.
China insisted yesterday that it was abiding by United Nations sanctions on North Korea despite a jump in its trade with the nuclear-armed nation that comes amid growing USA calls for Beijing to rein in its neighbor. "So much for China working with us - but we had to give it a try!"
Though Trump took a more conciliatory tone on the North Korea issue and China's role at a meeting with Chinese President Xi Jinping.