Military commanders from Western and Middle Eastern countries are meeting in Jordan to discuss the Syria conflict, as Western powers weigh military action in response to a suspected chemical weapons attack in Damascus.
As the U.S. considered its options and expressed increasing impatience with Syria's government, other countries scrambled to take positions.
Turkey said it would join an international coalition against Syria, even if the U.N. Security Council fails to reach consensus on the issue of suspected chemical weapons attacks, its foreign minister said in an interview published Monday in Turkey’s Milliyet newspaper.
"If a coalition is formed against Syria in this process, Turkey will take part in it," Ahmet Davutoglu told the Milliyet.
"After the inspection, the United Nations needs to make a decision on sanctions. If there's no such decision, other options will be on the agenda," Davutoglu said.
Separately, Russian Foreign Minister Sergei Lavrov urged restraint and said Moscow is "very concerned" about possible U.S. military action in Syria, Reuters reported, citing the ministry.
The meeting in Jordan was coordinated by Jordan's chief of staff Meshaal Mohamed al-Zaban and Gen. Lloyd Austin, head of Centcom -- the U.S. command responsible for 20 countries in the Middle East and Central Asia -- according to Jordanian officials.
U.S. Joint Chiefs of Staff Chairman Gen. Martin Dempsey was also set to participate, along with the chiefs of staff from Saudi Arabia, Qatar, Turkey, Britain, France, Germany, Italy and Canada, said an official cited by Jordan's state news agency.
Syria agreed on Sunday to let the United Nations inspect the site of the alleged chemical weapons attack, but a U.S. official said that such an offer was "too late to be credible" and that Washington was all but certain that the Syrian government had gassed its own people.
U.N. Secretary-General Ban Ki-moon, speaking at a news conference in Seoul on Monday, said: "I demand that all parties allow this mission to get on with the job so that we can begin to establish the facts."
"If proven, any use of chemical weapons by anyone under any circumstances is a serious violation of international law and an outrageous crime," Ban added. "We cannot allow impunity in what appears to be a grave crime against humanity."
The comments follow forceful remarks from Western powers, including Britain and France, which also said they believe Syrian President Bashar al-Assad's government was behind the supected attack, blamed for the deaths of hundreds of people last week.
U.S. Defense Secretary Chuck Hagel said on Sunday that the country's military was ready to take action against the Syrian government if ordered.
In Jordan, Foreign Minister Nasser Judeh said the meeting had been scheduled for months.
"The meeting is not a reaction to what happened recently in Syria. It is one of a series of meetings of the army chiefs of countries concerned about the situation in Syria," he said.
"At the same time, the meeting will discuss the situation and scenarios on the ground, especially after the recent dangerous developments. The army chiefs have to have comprehensive talks and examine the impact on the region."
Syria's information minister has said any U.S. military action would "create a ball of fire that will inflame the Middle East.”
The White House said Sunday it had "very little doubt" that the Syrian government was responsible for the assault that killed hundreds of civilians, as U.N. inspectors prepared to access the Damascus suburb where the purported nerve gas attack took place on Monday.
But a senior Obama administration official treated the Syrian decision with skepticism.
"If the Syrian government had nothing to hide and wanted to prove to the world that it had not used chemical weapons in this incident, it would have ceased its attacks on the area and granted immediate access to the UN. -- five days ago," the official said on condition of anonymity.
The Syrian government has denied responsibility for Wednesday's attack and blamed the rebels fighting Assad's forces of the same. The rebels have, however, held the regime forces responsible for the attack. The suburbs hit in the suspected chemical strike, collectively known as eastern Ghouta, are under the control of rebel fighters, and regime artillery and warplanes have pounded the area for days.
The U.N. inspectors will have to traverse both government-held and opposition-controlled turf to conduct their probe. Rebels have said they will help facilitate the visit.
Under Sunday's agreement with the U.N., the Syrian government "affirmed that it will provide the necessary cooperation, including the observance of the cessation of hostilities at the locations related to the incident," U.N. spokesman Martin Nesirky said in a statement.
The developments come amid heightened tension between the Syrian regime and the wider international community, with the U.S. said to have naval ships edging toward the strife-torn country as President Barack Obama weighs his options.
Both Assad's government and Iran, its stalwart regional ally, have issued stern warnings against intervention.
Iran said Sunday that if the U.S. crossed the so-called "red line" and intervened militarily in Syria it would have "severe consequences," the Fars news agency reported.
"America knows the limitation of the red line of the Syrian front and any crossing of Syria's red line will have severe consequences for the White House," said Massoud Jazayeri, deputy chief of staff of Iran's armed forces, reacting to statements by Western officials regarding the possibility of military intervention in Syria.
Obama has discussed the situation in Syria by telephone with British Prime Minister David Cameron on Saturday, the White House said. It was Obama's first known conversation with a foreign leader about Syria since the reports this week that hundreds of Syrians had been killed by an alleged chemical attack.
The White House said the two leaders expressed "grave concern" about the reported chemical weapons use, which both of their countries oppose.
Israeli Prime Minister Binyamin Netanyahu also called for immediate steps.
"Our finger or our hand is always on the pulse. Our finger is on the trigger but is always responsible," he said. "This situation must not continue."
Obama, however, is likely to encounter national resistance to a military intervention. A new Reuters/Ipsos poll released Saturday evening found that about 60 percent of Americans strongly oppose U.S. intervention in Syria, with only 9 percent in favor.
The Syrian government vehemently denies claims that it was responsible for the attack.
But Obama is under mounting pressure to act amid reports from opposition groups that more than 1,000 people were killed.
Bart Janssens, operations director for Doctors Without Borders (DWB), said Saturday that hospitals in Syria had reported thousands of patients displaying "neurotoxic symptoms" in line with mass exposure to nerve gas. Around 3,600 patients have been treated in three hospitals, he added. Of those, 355 have reportedly died, according to DWB.
If confirmed, it would be the largest chemical weapons attack since Iraqi leader Saddam Hussein gassed thousands of Kurds in the town of Halabja in 1988.
For a year now, Obama has threatened to punish Assad's regime if it resorted to its chemical weapons arsenal, among the world's vastest, saying use or even deployment of such weapons of mass destruction constituted a "red line" for him.
While the Reuters/Ipsos polls shows more Americans would back intervention if the chemical attacks are established -- up to 25 percent -- a remaining 46 percent would still oppose it.
The poll, taken Aug. 19-23, reveals a decline in support for U.S. action since Aug. 13, when an earlier survey showed that 30 percent of Americans backed intervention if chemical weapons were used. The two polls seem to suggest that the wrenching pictures of victims and the growing conflict in Syria have only hardened the resolve of many Americans not to get involved.
Officials have said Obama will decide how to respond once the facts are known.
"In coordination with international partners and mindful of the dozens of contemporaneous witness accounts and record of the symptoms of those killed, the U.S. intelligence community continues to gather facts to ascertain what occurred," the White House said after Obama's meeting, which included Secretary of State John Kerry, Defense Secretary Chuck Hagel and others.
To date, Hagel has declined to discuss specific force movements while saying that Obama had asked the Pentagon to prepare military options for Syria. U.S. defense officials told The Associated Press that the Navy had sent a fourth warship armed with ballistic missiles into the eastern Mediterranean Sea but without immediate orders for any missile launch into Syria.
Navy ships are capable of a variety of military actions, including launching Tomahawk cruise missiles as they did against Libya in 2011 as part of an international action that led to the overthrow of the Libyan government.
Hagel said the U.S. is coordinating with the international community to determine "what exactly did happen" near Damascus. Hagel left little doubt that he thinks chemical weapons were used in Syria. "It appears to be what happened -- use of chemical weapons," he said.
Al Jazeera and wire services