Global powers are set to clash next week as the world's chemical arms watchdog meets for the first time since it was rocked by allegations of Russian spying.
The Organisation for the Prevention of Chemical Weapons in The Hague faces difficult talks over a new investigative team that will start work next year to apportion blame for attacks in Syria.
Moscow has warned the OPCW risks becoming a "sinking Titanic" over new powers which would also allow it to probe incidents like the Salisbury nerve agent attack on a Russian double agent.
But the darkest shadow over the meeting will be the expulsion of four Russians accused by Dutch authorities in October of trying to hack into the watchdog's computer system.
New OPCW director-general Fernando Arias admitted in an interview with AFP on Monday that the watchdog was "going through a difficult moment" given recent events.
Key member states including Russia, the United States, Britain and France will all be able to have their say during the meeting, as will all 193 countries involved in the body.
Former Spanish diplomat Arias, who took over as chief earlier this year and will give the opening address at the meeting on Monday, insisted however that the toxic arms body was "more needed than ever".
Winner of the Nobel Peace Prize in 2013, the OPCW is responsible for upholding the 1997 Chemical Weapons Convention to end the use of all toxic arms.
So far it says it has overseen the destruction of 96.5 percent of the world's chemical arms stocks.
"The main goal is to consolidate the organisation and think that more than 21 years of success has to be preserved," Arias said.
- 'Very strong team' -
But in recent years it has seen its role expand to cover the investigation of a wave of chemicals attacks in the Syrian civil war, as well as the March 2018 Salisbury attack and the 2017 killing in Malaysia of a half-brother of North Korean leader Kim Jong Un.
Top of the agenda this week will be discussions on how to implement the new powers that member states agreed on at a special meeting in June to let the OPCW attribute blame for attacks.
Arias said the that the OPCW was setting up a "very small but very strong team that will be in charge of identifying the perpetrators in Syria", involving around nine or ten members.
The head of the team had already been picked and it would start work early next year, with a mandate to go back and try to point the finger for all chemical attacks in Syria since 2013.
The OPCW is due soon to release a full report on a chemical attack in the Syrian town of Douma in April. An interim report said chlorine was detected but not nerve agents.
But the watchdog will also be able to attribute blame for future attacks anywhere in the world, so long as it is asked to by the country on whose territory where the incident happened.
The Salisbury attack that sickened double agent Sergei Skripal and his daughter -- while left-over nerve agent left a British woman dead -- has added to the pressure for such powers.
"Salisbury means for us we have to adapt to the new risks and challenges," Arias said.
Russia and Iran, which are closely allied to Syria, have strongly opposed the new powers, saying they risk making the OPCW too political.