BEIJING, Feb. 27 -- China worked with Russia, Denmark, Norway on the fourth shipment of Syria's chemical weapons, a Foreign Ministry spokeswoman said here Thursday.

"Chinese frigate Yancheng worked with naval vessels from Russia, Denmark, Norway on the night of February 26, local time," said spokeswoman Hua Chunying at a daily press briefing.

The shipment of sulphur mustard, commonly known as "mustard gas," was confirmed by the Joint Mission of the Organization for the Prohibition of Chemical Weapons (OPCW) and the United Nations.

China welcomes efforts from all parties concerned, and would like to ensure the continued safe and smooth transport of chemical weapons, said Hua.

According to the OPCW plan, Syria's chemical weapons will be transported outside its territory to ensure their destruction in the "safest and soonest manner", no later than June 30.

In early January, Sigrid Kaag, the head of a joint mission to rid Syria of chemical weapons, told the 15-nation council that although the operation has been delayed, it is expected to meet its June deadline.

Syria renounced its chemical weapons material and joined 1992 Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons under an agreement brokered by Russia and the United States last year.