Former defence secretaries have backed the decision to wait for a report from UN weapons inspectors before taking action against Syria.
Tory Liam Fox said it was "reasonable" to wait but insisted the international community must "make a response" to the chemical weapons attack on the outskirts of Damascus.
Dr Fox, who quit as defence secretary in 2011, told BBC Radio 4's Today programme: "There has been a crime committed here. Chemical weapons are being used on the civilian population.
"It is against international law, it is a war crime. We have a duty as an international community to make a response to that.
"I think it is reasonable to wait until we have had the report of the UN inspectors but ultimately we will still have to make a response as an international community. We may have put it off for a few days from the British perspective but we still have to make a response."
Lord Reid, defence secretary under Tony Blair, said Labour leader Ed Miliband was right to force a delay, insisting it would "maximise the legitimacy" of the use of force.
He told Today: "I can't speak for Ed or for the party officially but I do think that his decision was a wise one and I do think that the Prime Minister David Cameron's decision to heed Ed Miliband's call to await the UN inspectors report was also a right one and a wise one.
"I say that especially because we are less than a week or so away from their conclusion, it's not a matter of months or years, and because waiting maximises the legitimacy of the use of force if it proves to be necessary.
"It also increases the prospect of greater international support for any action whereas jumping the gun, taking military action before the United Nations inspectors have had a chance to report, over a matter of 10 days, not 10 years or 10 months, jumping the gun on that would diminish both of those chances of legitimacy and support, especially if military action were to be followed by an inspectors' report that says that chemical weapons were not used and that is still possible."
Former defence secretary Michael Portillo said that the best solution would be to not intervene, but conceded: "All we're considering here are a range of bad options."
Speaking to Daybreak, he said: "I think we should be extremely wary of making yet another intervention in a Muslim country after Iran and Afghanistan... I think the Muslim world sees again and again the West attacking Muslim countries."
Portillo, who served as defence secretary under John Major, added that at the moment, if Bashar Assad was removed, Syria would "end up with someone much worse".
Former security minister Lord West stressed that evidence needed to be seen before any decision about action could be taken.
Also speaking to Daybreak, he said: "We absolutely need to see that evidence. We asked the UN to go and get it. Yes, alright, I think we're all pretty sure it was a chemical attack, but we should see it. I also think we want to see, in great clarity, the proof that the regime did it."
Conservatives attacked Mr Miliband for "playing politics" over the Commons motion, which resulted in David Cameron being forced to offer MPs a second vote before any direct involvement by British forces in action against Assad.
The official Conservative press office Twitter feed said: "Ed_Miliband is playing politics when he should be thinking about the national interest and global security."
Tory MP Nadhim Zahawi tweeted: "It's weak leadership to seek political advantage while every effort is being made to achieve consensus in the national interest Ed_Miliband."