British Foreign Secretary William Hague on Wednesday pressed the world’s chemical weapons watchdog to finish its probe into the alleged use of chlorine gas in Syria as urgently as possible.

British Foreign Secretary William Hague on Wednesday pressed the world's chemical weapons watchdog to finish its probe into the alleged use of chlorine gas in Syria as urgently as possible.

"The UK pushed hard to secure an investigation and we call on the OPCW to carry out its mandate with urgency," Hague said in a statement.

"Time is of the essence in establishing the full facts. The mission must be given full access to all sites and be allowed to carry out its investigation without any interference or delay."

The Organization for the Prohibition of Chemical Weapons (OPCW) announced Tuesday it is sending a fact-finding mission to Syria to probe allegations that the Syrian forces had used industrial chemicals on civilians.

For its part, Damascus accepted the OPCW request.

Britain said it would give the OPCW any assistance it needed to investigate the "sickening" allegations.

The OPCW and the United Nations are already destroying Syria's chemical weapons as part of a Russian-US disarmament deal agreed last August.