In April last year a report by the OPCW, the international chemical weapons watchdog, blamed the Assad regime for two sarin attacks on Ltamenah in northern Syria. The implications of this were especially serious because the attacks took place in 2017 – four years after the regime had formally renounced chemical weapons and three years after its declared stockpile had been destroyed.

The obvious conclusion was that the regime had either not declared some of its sarin at the time or had since resumed production.

This prompted a resolution from the OPCW’s governing body – the Conference of the States Parties – calling on Syria to declare the facilities where the weapons used in Ltamenah had been “developed, produced, stockpiled, and operationally stored for delivery”. It also called on Syria to declare all chemical weapons currently in its possession and to resolve all outstanding issues regarding its initial declaration.

Syria was given a 90-day deadline to comply, and when it failed to do so the states parties suspended its voting rights and banned it from holding any office within the OPCW.

It was the first time the OPCW had taken such action against a member state and the hope was that it would encourage Syria to cooperate. However, it had the opposite effect and, as the latest update from the OPCW shows, the regime responded by escalating its non-cooperation – on multiple fronts.

Syria's original chemical weapons declaration in 2013 was far from complete and has still not been certified as accurate by the OPCW's Declaration Assessment Team (DAT). As a result of discoveries by investigators it has so far been amended 17 times and a further 20 issues are still unresolved.

One of these outstanding issues concerns an underground site known as al-Nasiriyah1, previously declared by the regime as a former chemical weapons production facility. In July, Syria sent a note to the OPCW saying the site had been "flagrantly attacked" a month earlier by Israeli missiles. Since then, three letters from the OPCW requesting further information about the alleged damage have brought no response.

According to the regime, the same Israeli airstrikes also destroyed two gas cylinders that formed crucial evidence in connection with a suspected chlorine attack. The cylinders were at the centre of an investigation by the OPCW’s Fact-Finding Mission (FFM) regarding events in Douma in 2018. The FFM found “reasonable grounds” for believing a toxic chemical had been used as a weapon there, and the organisation’s Investigation and Identification Team (IIT) is now carrying out further work with a view to identifying those responsible.

The IIT had been seeking to transport the cylinders to OPCW headquarters for further examination but the Syrians refused to let them leave the country. As a result of that stand-off the cylinders had been placed in sealed containers and the Syrians were told not to tamper with them or move them without written consent from the OPCW.

The claim that they were destroyed in a strike on the Nasiriyah site is therefore puzzling because they were supposed to be stored at a different site 60km away. So far, Syria has ignored the OPCW's request for information about what remains of the cylinders and why they were moved without authorisation.

Since April, the OPCW has been seeking to hold a further round of consultations in Damascus about the continuing problems with its chemical weapons declaration. Initially it proposed to hold the discussions in May but Syria didn't reply until August, when it proposed to schedule them for October.

Since then, Syria has refused a visa for one member of the OPCW's team. The OPCW points out the person in question has been sent to Syria "on multiple occasions over the past seven years" and that Syria isn't entitled to determine the composition of its team. As an alternative, it has offered to receive a Syrian delegation at its headquarters in The Hague "for a limited three-to-four-day meeting" but it says "such a meeting cannot replace full-fledged deployments in the Syrian Arab Republic".

Visa issues are also causing problems at the OPCW's command post in Damascus, which is staffed on rotation. Twice this year, delays in issuing visas have resulted in periods when the command post had only UN support staff and no representative from the OPCW.