The United Nations Security Council recently unanimously passed a US-drafted resolution mandating tougher new sanctions against the People's Democratic Republic of Korea (DPRK).
China's Ministry of Commerce said that in line with the decision, Beijing is limiting exports of refined petroleum to the DPRK to 2 million barrels per year, beginning January 1, 2018.
China accounts for some 90 percent of North Korea's trade, making its cooperation critical to any efforts to derail Pyongyang's development of nuclear weapons and long-range missiles.
Being far and away North Korea's most important trade partner, Beijing has been reluctant to put much pressure on the regime, fearing it could destroy the relationship between the two countries and harm ordinary North Koreans.
But with Kim Jong-un crossing the line in exhibiting Pyongyang's military might, China has agreed to push the DPRK harder, and support the latest round of UN sanctions.
Chen Fengying, senior researcher with the China Institutes of Contemporary International Relations, said that after ordering banks to block transactions for accounts held by North Koreans and stopping imports of coal, iron ore and seafood, China is now entering a key phase on DPRK sanctions.
"These restrictions from China — one of its few remaining trading partners — could have more of an impact on North Koreans than we've previously seen," Chen said, cited by the South China Morning Post (SCMP).
In response to the newly-imposed sanctions, North Korea's official KCNA news agency threatened that the more sanctions are imposed on Pyongyang, the faster the country will move to complete its nuclear plans.
"The increased moves of the US and its vassal forces to impose sanctions and pressure on the DPRK will only increase our pace towards the ultimate completion of the state nuclear force," according to the KCNA statement.
Cui Tiankai, China's ambassador to the US, urged US President Donald Trump to stop continuously threatening North Korea and focus instead on building bridges of understanding and negotiation.