British Prime Minister David Cameron leaves 10 Downing Street in central London on August 29, 2013 after a Cabinet meeting to discuss a response to Syria following chemical attacks that Britain believe were launched by the Syrian regime. British lawmakers were on August 29, set to vote on Britain's response to chemical weapons attacks in Syria -- but any military action will require a second parliamentary vote. (Photo by Leon Neal/AFP/Getty Images)
Kim Hjelmgaard, USA TODAY
LONDON - Britain's government says the legal conditions have been clearly met for taking action against Syria for allegedly launching a chemical attack against its people.
However, the opposition Labour Party has said it wants to see "compelling evidence" of the Syrian regime's guilt before siding with Prime Minister David Cameron's governing coalition in a parliamentary vote.
Labour Party leader Ed Miliband said he was "determined we learn the lessons of the past, including (on) Iraq," where much ballyhooed evidence of weapons of mass destruction was subsequently deemed to be false.
The potential road block to war comes as Britain's Joint Intelligence Committee concluded that it is "highly likely" that Syrian President Bashar Assad's regime was responsible for the alleged chemical attack on Aug. 21 that may have killed hundreds. A document released by the JLC forms the British government's first published evidence indicating culpability for the attack.
Another separate document released by Downing Street Thursday that sets out the government's legal position says, "military intervention to strike specific targets" would be "legally justifiable."
Britain can go to war without the express consent or backing of parliament but in the wake of the Iraq war in 2003 there have been calls for the government to always seek the approval of parliament.
On Wednesday, Cameron reversed an earlier to decision to hold a single formal parliamentary vote that would specifically see authorization for British action prior to the conclusion of a report due from United Nations weapons inspectors.
Members of parliament will debate the motion Thursday, but a final vote from the United Kingdom on whether intervention should take place will now only come after U.N. investigators conclude their findings.
Downing Street has said that the back down reflected the government's "desire to proceed on a consensual basis," but the move followed threats by the Labour Party not to support a possible strike.
Labour are insisting that the U.N. inspectors be given more time to deliver their report to the U.N. Security Council.
A British draft resolution authorizing "necessary measures" to protect Syrian civilians was delivered to the Security Council in New York on Wednesday, where it was discussed.
Ahead of today's parliamentary vote - due to take place around 10 p.m. local time (5 p.m. ET) and being described as a vote of "principle" - the British government received a letter from the Syrian government seeking a peaceful solution to the crisis.
"We implore you to communicate through civilized dialogue rather than a monologue of blood and fire," the letter said, according to the BBC, who obtained a copy. The open letter was sent by the Syrian parliament speaker who also invited British MPs to send a delegation to the Mideast nation.
The U.N. inspection team will be leaving Syria by Saturday as its two-week mandate comes to an end, chief Ban Ki-moon said Thursday. Ban - speaking in Vienna on Thursday - said all opinions should be heard before anyone makes decisions on how to react to the alleged attacks.
President Obama said Wednesday he has concluded the Syrian regime is behind the attack. However, it's not clear if Western powers will wait for the U.N. experts' findings before launching a possible punitive military strike.
U.S. officials, the Associated Press reported, say the intelligence linking the Syrian President Bashar Assad or his inner circle to the alleged chemical weapons attack that killed at least 100 people is no "slam dunk."
The officials say, AP reported, that questions remain about who controls some of Syria's chemical weapons stores, and there are doubts about whether Assad himself ordered such a strike.
The U.S. is expected to reveal as early as Thursday evidence to support claims chemical weapons were used by Damascus.
Syria's Assad said his country will defend itself in the face of any aggression," Syrian State TV reported.