Facing strong opposition in the UK parliament, military action against the Syrian regime over the alleged use of chemical weapons could be delayed. Meanwhile, US president Barack Obama said he has not yet made a final decision about the military attack.

On Thursday, the House of Commons will be asked by the government to approve a "strong humanitarian response" to the Syrian government’s alleged war crimes.

However, British opposition leader Ed Miliband said he would call on his MPs to vote against the government motion if the amendment calling for the delay of any military action is defeated, the Guardian reports.

"We will continue to scrutinise this motion but at 5.15pm David Cameron totally ruled out a second vote, an hour and a half later he changed his mind,” a Labour source told the Guardian. “Ed was determined to do the right thing. It has taken Labour forcing a vote to force the government to do the right thing."

The delay of parliamentary approval could push back the military response timetable until next Tuesday when MPs are expected to have another vote.



Among other conditions the Labour Party said it would support military action only if members of the UN Security Council saw the chemical weapons inspectors report first.

“The United Nations Security Council must have the opportunity immediately to consider that briefing and that every effort should be made to secure a Security Council Resolution backing military action before any such action is taken,” the motion says.

Obama: 'No final decision yet'

Meanwhile, US President Obama said he has not made a decision on whether to order a strike in Syria, although the US has concluded that the Syrian government carried out chemical weapons attacks near Damascus last week.

"We have not yet made a decision, but the international norm against the use of chemical weapons needs to be kept in place,” Obama said in an interview with PBS Wednesday evening.

Obama said direct military engagement with Syrian forces during their civil conflict would not ease tensions on the ground.

"If we are saying in a clear and decisive but very limited way, we send a shot across the bow saying, 'Stop doing this,' that can have a positive impact on our national security over the long term," he said.

Obama disavowed an open-ended conflict with Syria while reiterating that those who use chemical weapons must be held responsible.

"I have no interest in any open-ended conflict in Syria, but we do have to make sure that when countries break international norms on weapons like chemical weapons that could threaten us, that they are held accountable," Obama said, adding that Syria has "one of the largest stockpiles in the world of chemical weapons.”

While the UN team is still due to release any details of the August 21 chemical attack, Obama has claimed that the US, having “looked at all the evidence,” does not believe the opposition possesses chemical weapons “of that sort.”

“We do not believe that, given the delivery systems, using rockets, that the opposition could have carried out these attacks,” Obama said. “We have concluded that the Syrian government in fact carried these out. And if that’s so, then there need to be international consequences.”

In a US State Department briefing Wednesday, a spokesperson admitted the department does not know who in the Syrian government could have ordered the chemical attack.



"The commander-in-chief of any military is ultimately responsible for decisions made under their leadership, even if ... he's not the one that pushes the button or said, 'Go,' on this," Marie Harf said. "I don't know what the facts are here. I'm just, broadly speaking, saying that he is responsible for the actions of his regime. I'm not intimately familiar with the command and control structure of the Syrian military. I'm just not. But again, he is responsible ultimately for the decisions that are made."

Earlier, US Speaker of the House John Boehner has written a letter to President Obama asking for clarification on a host of questions ahead of any attack on Syria.

"Now, having again determined your red line has been crossed, should a decisive response involve the use of the United States military, it is essential that you provide a clear, unambiguous explanation of how military action – which is a means, not a policy – will secure US objectives and how it fits into your overall policy."

White House officials are due to brief bipartisan congressional leaders and heads of pertinent committees on Thursday regarding Syria's alleged use of chemical weapons and potential options for responding.



Russia urges patience on ‘all necessary measures’ UN resolution on Syria

Earlier on Wednesday, Russian Foreign Minister Sergey Lavrov urged his UK counterpart William Hague to wait for the results of the UN chemical weapons inspection in Syria, before submitting a Security Council resolution that would permit the use of force against President Bashar Assad.

Hague phoned Lavrov on Wednesday night, hours after presenting a resolution to use “all necessary measures under Chapter 7 of the UN Charter to protect civilians from chemical weapons.”

The five members of the UN Permanent Security Council – which will have the final say in whether any resolution is implemented – met in New York on Wednesday, to unofficially discuss the text of the draft resolution. None of the officials present revealed the result of the talks, though earlier this week Lavrov warned against military intervention “in line with the Libya and Iraq scenario.” He has also claimed to be unconvinced by US assertions that government forces were behind the attack.



United Nations Secretary-General Ban Ki-moon has also urged the sides to let the inspectors, who he said had “collected valuable samples,” finish their job, before submitting any proposal for intervention.

A United Nations chemical weapons inspection is currently underway in the Syrian capital, and is expected to produce a report on the alleged attack by Sunday at the latest.

Meanwhile, Washington sources claim the White House is preparing to present a portfolio of evidence indicting the government for the chemical attack in the coming days. Among the materials that are expected to be made public are intercepted phone conversations, photos and eyewitness accounts from August 21.