AMMAN (Reuters) - Syria said on Thursday it was ready to cooperate with the global chemical weapons watchdog over accusations it had used poison gas against insurgent held areas.

A Syrian foreign ministry statement said Damascus was ready to cooperate with a team of the Organization for the Prohibition of Chemical Weapons (OPCW) currently in Syria and looking into incidents Damascus blames on "terror groups and their foreign operatives".

A joint investigation by the United Nations and the chemical weapons watchdog last month found Syrian government troops were responsible for two toxic gas attacks and that Islamic State militants had used sulfur mustard gas, according to a report seen by Reuters.

The year-long U.N. and OPCW inquiry - unanimously authorized by the U.N. Security Council - focused on nine attacks in seven areas of Syria.

The results set the stage for a Security Council showdown between the five veto-wielding powers, likely pitting Russia and China against the United States, Britain and France over whether sanctions should be imposed after the inquiry.

Diplomatic sources say there have been discussions between Washington and other powers in the Security Council on a resolution that would impose sanctions, moves that have long been opposed by Moscow, a staunch ally of President Bashar al Assad's government.

Syrian defense workers operating in rebel-held areas said Syrian helicopters dropped bombs with chlorine on the Sukri neighborhood of Aleppo on Tuesday.

The Syrian Observatory for Human Rights said on Wednesday that one person had died as a result of the attack that caused dozens of cases of suffocation. The Syrian army denied the accusations.

(Reporting by Suleiman Al-Khalidi; editing by Ralph Boulton)