The UK, US and France have presented plans for a ceasefire in Syria in the wake of their joint airstrikes on the war-torn country.
The three allies have produced a draft UN resolution which also includes proposals for an independent investigation into alleged toxic gas attacks to identify perpetrators.
The Organisation for the Prohibition of Chemical Weapons would be instructed to report within 30 days whether President Bashar al Assad’s government has fully disclosed its chemical weapons stockpile.
The draft document also calls for medical evacuations and the safe passage for aid convoys to all areas of Syria.
A ceasefire resolution that was adopted in February but never materialised should also be enforced, it adds.
The document “demands” that the Assad regime engage in peace talks “in good faith, constructively and without pre-conditions”.
Negotiations on the draft resolution are set to begin on Monday, but diplomats remain unclear when the UN Security Council would vote on the proposal.
Western diplomats have said they were ready to allow time for negotiations to make every effort to bring Russia aboard.
Russia has used its veto 12 times at the Security Council to block action targeting its Syrian ally.
It comes after the US, UK and French launched strikes on three sites linked to Syria’s chemical weapons programme.
On Saturday, the UN Security Council overwhelmingly rejected a Russian resolution calling for condemnation of “aggression” by the three allies.
Only China and Bolivia voted in favour, while three other countries abstained. A resolution needs nine ‘yes’ votes to be passed.
The US has said it is “locked and loaded” for further strikes if the Syrian regime uses poisonous gas again.
Foreign Secretary Boris Johnson said Britain had a duty to show that Syria had not “got away with it” and it was standing up against Assad’s “barbarism”.
In an article for The Sunday Telegraph, he said: “Unless we act there is a risk of moral contamination, a coarsening and corruption of what we have until now thought to be acceptable.”
The British government also published its legal position on the airstrikes after Labour leader Jeremy Corbyn called the military action “legally questionable”.
The Government said the UK is allowed under international law “on an exceptional basis” to take measures to end “overwhelming humanitarian suffering” if certain conditions have been met.
Prime Minister Theresa May will face questions from MPs on Monday, when parliament reconvenes after a break.
Protest group Stop the War has called a demonstration outside parliament on the same day.