United Nations, Dec 23: With unprecedented Chinese backing, the Security Council tightened the economic chokehold on North Korea by unanimously voting on Friday to impose the strictest sanctions on North Korea aiming to cut off most fuel supplies and ban major exports following Pyongyang's latest missile test. The resolution introduced by the US after intense lobbying won the support of China, which has had a special relationship with North Korea and had in the past opposed or tried to soften sanctions. The new round of restrictions further tightens the sanctions imposed last month, which had been lightened to gain the support of Moscow and Beijing. "This resolution ratchets up the pressure on North Korea even further, building on our last resolution, which included the strongest sanctions ever imposed on them," US Permanent Representative Nikki Haley, who piloted it, told the Council. Haley acknowledged Beijing's cooperation saying: "I would like to specifically thank my Chinese colleagues for working with us on the negotiations." Beijing's vote for the tougher sanctions indicates that its direct influence with North Korean dictator Kim Jong-un is waning and that China is recognising the global dangers from North Korea's nuclear and missile arsenals. The Charge d'Affaires at the Chinese Mission, Wu Haitao, said there was a risk of the situation spiraling out of control. The resolution would reduce North Korea's refined petroleum imports by 90 per cent from the 2017 mid-year level to 500,000 barrels per year, and it authorises the Council to further reduce petroleum imports if it carried out any missile or nuclear tests. All North Korean exports and most imports are also banned under the resolution. It also requires the expulsion by the end of 2019 of all North Korean expatriate workers who are estimated to earn the government $500 million each year. Fifteen North Koreans, who are bankers or are involved in weapons developments were put on a sanctions list banning their travel and freezing their assets. The resolution also requires all nations to seize ships smuggling goods to North Korea. Wu called for an end to all rhetoric that would escalate tensions and said that "tough posturing" only led to Pyongyang advancing its proliferation activities. Haley softened her tone this time at the Council without the past threats of violent retaliation that matched Pyongyang's rhetoric. The high-level Council meeting on North Korea earlier this month attended by US Secretary of Rex Tillerson and Japanese Foreign Minister Taro Kono paved the way for the latest sanctions because it sent a very clear message that the international community would not accept a nuclearised North Korea, Japan's Permanent Representative Koro Bessho said at a news conference after the vote. After the November 28 intercontinental ballistic missile test the campaign for the latest round of sanction began, he said.