Imports from the North shrank 81.6 percent to $54 million in December, while exports to Pyongyang contracted by 23.4 percent to $260 million, AP said, citing a spokesman for the Chinese customs agency, Huang Songping.
"The meeting will bring together nations from across the globe to demonstrate global solidarity against North Korea's risky and illegal nuclear and ballistic missile programs", the statement said.
Japan has also reportedly criticized the meeting.
While Chinese exports to North Korea increased in 2017 by 8.3 percent, imports slumped 33 percent from the year earlier, Market Watch reports.
North Korea will not face any difficulties even if foreign nations introduce anti-Pyongyang sanctions that could last for a century, North Korean supreme leader Kim Jong-un said Friday.
Despite the loss of nearly all trade, the impoverished North has pressed ahead with weapons development that Kim's regime sees as necessary for its survival in the face of USA pressure.
Tensions sharply escalated a year ago as Pyongyang tested its sixth nuclear weapon and three intercontinental ballistic missiles capable of striking the mainland U.S.
China has "closed some sanctions gaps", Brian Hook, director of policy planning for U.S. Secretary of State Rex Tillerson, told reporters in Washington on Thursday.
While China has rejected calls from past presidents to do more, Beijing is starting to go along with US initiatives to put pressure on North Korea, even accepting USA demands for restrictions on oil exports to the North. According to a Russian expert, who visited Pyongyang recently and spoken to senior North Korean figures, the overall mood at the Kim Jong-un regime suggests there is no doubt on whether a full-fledged conflict will break out.
A different official, asking not to have the information attributed to them, said that "we did not expect China to attend this meeting".