Britain and its allies lead a high-stakes diplomatic drive Tuesday to give the world's global chemical watchdog the power to identify those behind toxic arms attacks, setting up a new showdown with Russia.
The meeting comes as inspectors from the Organisation for the Prohibition of Chemical Weapons (OPCW) are expected to unveil a long-awaited report into an alleged sarin and chlorine gas attack in April in the Syrian town of Douma, in which medics and rescuers say 40 people were killed.
British Foreign Secretary Boris Johnson will head up the British delegation to a rare special session of the OPCW's top policy-making body in The Hague, the British government has confirmed.
London called the talks of the OPCW's state party members in the wake of the nerve agent attack on former Russian double agent Sergei Skripal and his daughter in the English town of Salisbury, which Britain and its allies have blamed on Russia.
There has however been growing international concern about repeated allegations of the use of poison gases in the Iraq and Syria conflicts, compounded by the 2017 assassination of the North Korean leader's half-brother in a rare nerve agent attack in Kuala Lumpur airport blamed on Pyongyang.
It is feared that although deadly chemical weapons were once largely shunned as taboo after decimating forces during World War I, their use is once again becoming gradually normalised in the absence of any effective way of holding perpetrators to account.
A draft British proposal to the meeting, which opens Tuesday, suggests that the OPCW "begins attributing responsibility for chemical weapons attacks in Syria," Johnson said in a tweet earlier this month.
"With proven technical expertise on chemical weapons the OPCW is the right body to study who is behind an attack," he added.
"The mandate of the OPCW must be adapted to the challenges of the 21st century," said a French diplomat, asking not to be named.
"It was conceived in an entirely different context to independently verify the proper destruction by the major powers during the Cold War of their chemical weapons stocks... the OPCW's structures and missions must be adapted to the current situation."
Tensions are likely to run high, and the talks will move behind closed doors on Wednesday and possibly linger on until Thursday for a key vote on the British draft decision. It is only the fourth time in the body's history that such a special session has been convened.
Russia, which has accused the volunteer Syrian White Helmets rescuers of mocking up the Douma attack, has already angrily denounced the talks in The Hague, saying "the attributive function goes beyond the mandate of the OPCW".
In a statement from the Russian embassy in the Netherlands, Moscow contended that the rules governing the OPCW can be changed only by amending the convention itself.
And it has accused Britain and its allies of "fanning anti-Syria and anti-Russia hysteria".
A two-thirds majority, minus any abstentions, is needed for Britain's draft to pass, with about 130 countries out of the OPCW's 193 members reportedly saying they will attend.
But sources say Russia is already working behind the scenes to garner support to defeat the proposal.
Moscow wielded its veto power late last year at the UN Security Council to effectively kill off a previous joint UN-OPCW panel aimed at identifying those behind attacks in Syria.
Before its mandate expired in December, the panel known as the JIM (Joint Investigative Mechanism) had determined that the Syrian government had used chlorine or sarin gas at least four times against its own civilians. The Islamic State group used mustard gas in 2015.
Outgoing OPCW head Ahmet Uzumcu has said the current situation of impunity for use of chemical weapons is "unsustainable", warning that "a culture of impunity cannot be allowed to develop around the use of chemical weapons".
An independent body of experts from around the world, the OPCW began in 1997 to implement the Chemical Weapons Convention banning the production, stockpiling and use of toxic arms. It won the 2013 Nobel Peace Prize for its work.