Two months into a US airstrike campaign targeting radical Islamists in Syria, some American officials are growing restless with what they see as a one-sided effort that has handed President Bashar Assad's regime the upper hand in the country's civil war.

But despite reports of a contemplated strategy change, experts say the Obama administration has precious few alternatives to its current course of action.

In an article published Wednesday, CNN cited several anonymous US officials and diplomats who told the outlet that the Obama administration could be reconsidering its policy on Syria's civil war and coming to the conclusion that the Islamic State cannot be defeated without the removal of Assad.

CNN called the review reportedly conducted by Obama's national security team, "a tacit admission that the initial strategy of trying to confront ISIS first in Iraq and then take the group's fighters on in Syria, without also focusing on the removal of al-Assad, was a miscalculation."

'All these anonymously sourced stories are just bureaucratic infighting, making things out as policy.'

The US has also faced criticism from Turkey and Gulf states because of its focus on fighting Islamist militias rather than Assad.

On Thursday, however, Defense Secretary Chuck Hagel told the House Arms Services Committee, which oversees the Department of Defense, there was no such shift underway.

"Because we do not have a partner government to work with, or regular military partners as we do in Iraq, in the near term, our military aims in Syria are limited to isolating and destroying ISIL's safe havens," said Hagel, referring to the Islamic State, also called ISIS.

William McCants, a fellow at the Brookings Institution's Center for Middle East Policy, told VICE News that stories like CNN's are misleading.

"All these anonymously sourced stories are just bureaucratic infighting, making things out as policy," McCants said. "There are certainly parts of the executive branch that want that to happen and have wanted that to happen for a long time, but I don't see a big shift in policy."

American efforts to train "moderate" Syrian rebels while bombing more extreme elements have so far offered few successes. Earlier this month, fighters from al Qaeda linked Jabhat al Nusra dealt a stinging defeat to CIA-backed rebels in the northern province of Idlib.

US airstrikes have also targeted al Nusra, a development that may have given the group greater support among Syrians who see the airstrikes as benefiting the government in Damascus.

"When American airstrikes targeted al Nusra, people felt solidarity with them because Nusra are fighting the regime, and the strikes are helping the regime," Raed al Fares, an activist leader in northwestern Syria, told the Washington Post.

"Now people think that whoever in the Free Syrian Army gets support from the US is an agent of the regime," al Fares said, referencing the loosely affiliated rebel groups opposed to Assad.

With each defeat of moderate rebels, the conflict in Syria increasingly pits two forces against one another — Islamist extremists and the Syrian government — which the US publicly says must be removed.

"Somebody's going to benefit from the bombs being dropped, and it's Bashar," Juan Cole, professor of History at the University of Michigan and editor of a popular Mideast affairs blog, told VICE News.

That dilemma was underscored in September, when Obama told 60 Minutes: "For a long-term political settlement, for Syria to remain unified, it is not possible that Assad presides over that entire process."

But Obama also indicated that groups like the Islamic State pose "immediate threats to the United States."

"What I'm saying is they are all connected but there's a more immediate concern that has to be dealt with," Obama said.

Meanwhile, amid talks of a UN-proposed "freeze" in the contested city of Aleppo, government forces have stepped up aerial assaults on rebel areas, attempting to disrupt supply lines. Losing Aleppo would be a critical setback for opposition forces.

On Saturday, the UK-based Syrian Observatory for Human Rights said it had counted more than 500 airstrikes carried out by government planes and helicopters since the start of the month. On November 9, the group estimated such attacks in Aleppo province had left some 121 killed and wounded — many of them civilians.

"The regime has no reason to compromise at this point," Cole said. "It's reasserted itself in central Syria, and is no longer in danger of being cut off from its supply routes. As long as that's the case, the war is over — there's nothing the rebels can do to threaten the regime."

It came as a surprise, then, when it emerged this week that Russia has floated the idea of a so-called "Moscow I" summit on Syria, modelled after largely failed peace initiates in Geneva. Russia is reportedly planning to invite Syrian Foreign Minister Walid al Muallem and members of the moderate opposition, including Moaz al Khatib, former president of the National Coalition for Syrian Revolutionary and Opposition Forces.

A spokesperson for the UN Syria envoy, Stefan de Mistura, told VICE News the organization is aware of chatter about such a meeting, but not of a concrete date or agenda.

Joseph Bahout, visiting scholar at Carnegie Endowment for International Peace's Middle East Program and former consultant at the French Ministry of Affairs, told VICE News the Russians are testing the waters, and trying to capitalize — if only theatrically — on the West's failures to broker anything approaching a cessation of hostilities.

"There were meetings in Moscow where there was a proposal floated that involved accepting Bashar for a transitory period," Bahout said.

'Somebody's going to benefit from the bombs being dropped, and it's Bashar.'

Bahout added that the specter of Moscow talks is overinflated, especially considering those opposition figures — like al Khatib — who are being considered by Moscow for the summit are not largely seen by rebels as representing them.

In Iraq, where American and coalition forces are also bombing Islamic State targets, the US has tacitly cooperated with Iran in its efforts to turn back the Sunni extremist group.

"There is one strategy on Iraq and something that is not a strategy on Syria," said Bahout. "The problem is this dual approach. On Iraq it is firm and more complete and has a political component that includes a better government and inclusion of Sunni tribes."

"In Syria, it's only striking ISIS in some places," Bahout said. "This is another contradiction in strategy."

Shiite-dominated Iran is seen as one of Assad's principal backers.

"The problem is that in Syria, Iran is allied with Bashar, who the US wants to see overthrown," Cole said. "If you go after ISIL and Bashar at the same time you are going to anger the Iranians and reduce their willingness to help out in Iraq."

Relations with Iran are already delicate due to ongoing negotiations over Tehran's nuclear program. A spokesperson for Russia's foreign ministry said the November 24 deadline for an agreement between Iran and a group of six countries — the UK, China, France, Germany, Russia and the United States — is likely to pass without a compromise reached.