And U.S. officials all but tell U.N. inspectors in Syria to get out of the way.

For almost two years, President Obama has avoided direct military involvement in Syria's bloody civil war as the death toll skyrocketed.

Now, after a suspected chemical attack last week obliterated the "red line" Obama set, a flurry of comments and activity seem to be laying the groundwork for a military strike.

Security officials in London will meet Wednesday to hash out options. And on the ground in Syria, U.N. inspectors aimed to once again comb through the rubble of a Damascus suburb in search of evidence that chemical weapons were used in an attack last week that killed more than 1,300 people.

But U.S. officials aren't placing much stock in the findings.

"We clearly value the U.N.'s work -- we've said that from the beginning -- when it comes to investigating chemical weapons in Syria. But we've reached a point now where we believe too much time has passed for the investigation to be credible and that it's clear the security situation isn't safe for the team in Syria," State Department spokeswoman Marie Harf said Tuesday.

Instead, the U.S. and key allies all agree something ought to be done -- and increasingly that is leaning toward a military solution.

U.S. forces are ready, if an order to strike comes down, Defense Secretary Chuck Hagel told the BBC on Tuesday. A senior Defense Department official told CNN that any strike could be completed "within several days."

On Wednesday, Australia said it won't send troops. But the British prime minister's office was more circumspect in its statement.

Britain has drafted a United Nations Security Council resolution "condemning the chemical weapons attack by Assad and authorizing necessary measures to protect civilians," David Cameron tweeted Wednesday. The resolution will be put forward at the U.N. in New York later on Wednesday, he said.

The options

Going through the United Nations probably won't be a viable option for the United States and its allies.

Should anything be proposed to the Security Council, Russia -- which is a close ally of Syria and has a permanent seat on the council -- could block it. China, which also has a seat on the council, would probably object to any military measures against Syria.

At the same time, a military coalition is taking shape among Western powers.

Along with Britain, France has also signaled it would join Western military intervention against forces supporting Syrian President Bashar al-Assad.

French President Francois Hollande said Tuesday that France is "ready to punish those who made the decision to gas these innocent people."

NATO ambassadors are to take up the topic of Syria at their regular Wednesday meeting.

Obama continues to review options, White House press secretary Jay Carney said, adding that "nothing has been decided."

Those options include peaceful diplomacy.

The next step is the release of an intelligence report the United States conducted independently of the U.N. It is to come out later this week, said a Washington official who was not authorized to speak to the media.

Missile strikes on Syria likely response to chemical attack

The manner

The White House has ruled out sending ground troops to Syria or implementing a no-fly zone to blunt al-Assad's aerial superiority over rebels.

Sen. Jack Reed of Rhode Island believes that the most realistic option would be cruise missiles launched from U.S. Navy ships at sea, noting that "we can have precision weapons that could be fired and keep our aircraft out of Syrian airspace and away from their anti-aircraft systems."

"The most effective targets would have command-and-control, because you could send a signal to the Syrian regime that if they don't agree to international standards, if they don't make it clear and make it obvious that they're not going to use these weapons, and that we can inflict additional damage on their command-and-control," he added.

Intervening in Middle East turmoil: Mission impossible?

The resistance

Syrian Foreign Minister Walid Moallem says the United States has trumped up charges against his government as an excuse for an already desired intervention.

"We all hear the drums of war," he said Tuesday. "They want to attack Syria. I believe to use chemical weapons as a pretext is not right."

Syrian officials have steadfastly denied using chemical weapons in this or other cases.

If foreign powers do strike the Middle Eastern nation, its foreign minister said the government and its forces will fight back.

"Syria is not easy to swallow," said Moallem. "We have the materials to defend ourselves. We will surprise others."

It has backers in Russia and Iran.

Russia is leading the charge internationally against a strike, with Foreign Minister Sergey Lavrov saying there is no proof yet Syria's government is behind last week's chemical attack. It accused Washington of trying to "create artificial groundless excuses for military intervention."

"The West handles the Islamic world the way a monkey handles a grenade," Russian Deputy Prime Minister Dmitry Rogozin tweeted.

And Iranian Foreign Minister Mohammad Javad Zarif warned Wednesday of "graver conditions" should strikes be carried out.

"If any country attacks another when it wants, that is like the Middle Ages," he said.

The pushback

Some are pushing back at home and abroad on the White House's talk of intervention.

Military involvement seems unpopular with Americans. In opinion polls, few citizens approve of it.

Some members of Congress say that before Obama orders any strike, he should go through them first.

A group of 31 Republican and six Democratic lawmakers on Tuesday sent a letter to the president urging him "to consult and receive authorization" before signing off on any military action.

Some fear a U.S. strike could stoke the conflict, not quell it. Others don't want the administration to go it alone. Reed of Rhode Island said NATO allies must be involved, as well as members of the Arab League.

Former U.S. Rep. Newt Gingrich of Georgia is dead set against it. "Both sides are bad," he wrote in a commentary for CNN. "There is no victory to be had there."

U.N. Secretary General Ban Ki-moon seemed to ask for a reprieve Wednesday for the sake of his inspectors in Syria. "The team needs time to do its job," he said from The Hague, where he visited the International Criminal Court.

He said the U.N. has already collected valuable evidence.

Source:CNN News International