Prime Minister David Cameron had summoned MPs to return early from their summer break in order to vote in the House of Commons for British involvement in possible military strikes against Syria within days.
Cameron was forced to make a tactical retreat on the issue as a result of pressure from Labour party leader Ed Miliband, whose party has demanded six concessions for supporting the government over Syria.
The demands of the Labour party include a UN Security Council vote on the inspectors' report; a further report to the Commons and a second vote before Britain takes part in any military action; "compelling evidence" that the Assad regime was responsible for last week's attack; and a "clear basis in international law" for intervention.
UK foreign secretary William Hague said there would be "further discussions in New York over the coming days" but added: "We are clear that if there isn't agreement at the UN, then we still have a responsibility. It's very important not to take so long to respond that people confuse what the eventual response is about".
"These are no easy choices to make and there is no risk-free choice to make," he said.
Cameron had spoken to US President Barack Obama on the situation in Syria before making a case to parliament for targeted military action to halt the alleged use of chemical weapons.
Ahead of today's parliamentary vote, MPs will be given a dossier of evidence by Downing Street that Whitehall sources have described as "utterly compelling" proof of Assad's involvement in chemical atrocities against his own people.
United Nations inspectors are in Syria, investigating last week's alleged chemical weapons attack in the suburbs of Damascus, in which hundreds of civilians were killed.
Meanwhile, the UK's Ministry of Defence confirmed it was taking the "precautionary measure" of flying in six Royal Air Force (RAF) Typhoon jets to its base in Cyprus.
