President Barack Obama has asked the U.S. Congress to approve military strikes against the Syrian government over the alleged use of chemical weapons.
Obama said the alleged attack August 21 was so “heinous” that he wants to respond with what he described as a “limited” military operation. Obama said the message must be sent that using chemical weapons is intolerable.
Calling the UN Security Council "paralyzed" on the issue, Obama said limited U.S. military strikes would not require authorization from the Security Council.
Later August 31, the White House sent a draft measure to Congress that calls for giving Obama formal authorization to use military force in Syria to "deter, disrupt, prevent and degrade" the potential for further chemical attacks.
The Senate and House of Representatives are expected to debate and vote on the question beginning the week of September 9.
Obama administration officials say they believe congressional lawmakers will support a military strike. But approval of a measure is not assured.
Divisions are evident among many lawmakers, with some not yet committed to a strike and others seeking a major operation aimed at ending the rule of the Assad regime.
Additionally, recent opinion polls show most Americans do not believe military intervention in Syria would be in U.S. interests.
Earlier, Russian President Vladimir Putin challenged the United States to present evidence to the United Nations to back their claims that the Syrian government used chemical weapons.
During a visit to Vladivostok, Putin said it would be "utter nonsense" for the Syrian government to use chemical weapons when its forces are winning in the fight against rebels.
"Common sense speaks for itself. The Syrian government forces are advancing, in some regions they have surrounded the rebels. In these conditions, to give a winning card to those who are calling for a military intervention is utter nonsense," Putin said.
"It does not fit any logic, especially on the day of the arrival of the UN inspectors, so I am convinced that it is just a provocation by those who want to pull other countries into the Syrian conflict, who want to gain support from powerful international players, first of all -- the United States."
A U.S. intelligence report said U.S. officials had "high confidence" the Syrian regime carried out the August 21 attack, which the report says killed 1,429 people.
On August 30, Obama said Washington was considering the possibility of what he called a "limited, narrow" military operation to send the message that chemical weapons should not be used.
"The world has an obligation to make sure that we maintain the norm against the use of chemical weapons," Obama said. "Now, I have not made a final decision about various actions that might be taken to help enforce that norm."
The Syrian government has condemned the U.S. report as "fabricated" and based on "lies" put forward by rebels.
The Syrian government has denied involvement in any chemical attack, instead accusing rebels of being behind such attacks in a bid to trigger Western intervention and reverse battlefield losses.
Putin said Obama, a Nobel Peace Prize laureate, should consider potential victims of a military strike.
Russia, a longtime ally and arms supplier to the Syrian government, has said any use of military force without UN approval would be a breach on international law.
Russia has blocked efforts in the UN Security Council to agree on a resolution that would authorize foreign strikes in Syria.
Putin said plans to deliver strikes against Syria have been prompted by recent Syrian government's advances against rebels.
He said the British Parliament's decision not to sanction participation in military strikes was unexpected, and showed "there are people of common sense there."
A Russian Foreign Ministry statement on August 30 called for Washington to await the results of a United Nations investigation into the alleged attack.
The lack of a Security Council resolution has limited the number of countries that have publicly said they would back a U.S.-led military operation.
Only France has publicly indicated it is ready to join any U.S. attack. Britain said it would not be involved after lawmakers voted down a motion on August 29.
In Turkey, Prime Minister Recep Tayyip Erdogan said any international military intervention should be aimed at bringing an end to the rule of Syrian President Bashar al-Assad.
Erdogan said the point of any military action should be to stop the bloodshed and weaken the regime "to the point where it gives up." He said an operation of one or two days "will not be enough."
Erdogan cited the NATO operation against Serbia during the 1999 Kosovo war as an example. That war ultimately led to a change in government in Belgrade.
Earlier on August 31, United Nations inspectors who have been probing the alleged chemical-weapons attack near Damascus left Syria, crossing into Lebanon after carrying out four days of inspections.
Later, they arrived in the Netherlands from Syria and spoke with UN Secretary General Ban Ki-moon about their investigation.
Martin Nesirky, Ban's spokesman, said the team left Syria early on August 31 in order to safely transport medical and soil samples to two designated laboratories in Europe where they will be analyzed.
"The team which is now in the Netherlands will be spending the day [on September 1] collating the samples and other evidence which they have, prior to the testing in the laboratories in Europe," Nesirky said.
"The United Nations mission is uniquely capable of establishing, in an impartial and credible manner, the facts of any use of chemical weapons based directly on evidence collected from the ground."
Speaking at United Nations headquarters in New York, Nesirky told journalists that the UN chemical-weapons experts plan to return to Syria to continue their investigation, because it is not yet completed. He did not specify when they would return.
"We have given an undertaking -- the team has given an undertaking -- to the Syrian authorities that it will return to complete its investigation of all pending allegations. That remains the case," he said.
Nesirky stressed that the UN chemical-weapons experts had a mandate to confirm whether or not chemical weapons have been used in Syria.
He said the investigators would not extend their probe to the question of who was responsible, if anyone, for launching chemical attacks in Syria.
"The mandate is the mandate. The team and the secretary-general will abide by that mandate," Nesirky said.
With reporting by Reuters, AP, Interfax, AFP, and dpa