Threatened by rebel advances last year, Assad is now pumped up with confidence after Russian air strikes reversed the tide

* Balance of power tilts in Assad's favour

* Russia hands Assad the initiative at talks

* War in its sixth year

* Analysts see no prospect of a solution now

* Russia pull-back jolted Assad

* Sent message of rationality to U.S.

By Samia Nakhoul

CAIRO, April 8 (Reuters) - As the Syria peace talks resume next week, President Bashar al-Assad, backed militarily by Iran and Russia, shows no willingness to compromise, much less step aside to allow a transition Western powers claim is the solution to the conflict.

Threatened by rebel advances last year, Assad is now pumped up with confidence after Russian air strikes reversed the tide and enabled his army to recover lost ground from Sunni insurgents as well as the jihadis of Islamic State.

While Syria experts doubt he can recapture the whole country without an unlikely full-scale ground intervention by Russia and Iran, they also doubt President Vladimir Putin will force him out - unless there is a clear path to stability, which could take years.

Instead, Russia's dramatic military intervention last September -- after five years of inconclusive fighting between Assad and fragmented rebel groups mostly from Syria's Sunni majority -- has tilted the balance of power in his favour and given him the upper hand at the talks in Geneva.

The main target of the Russian air force bombardment was mainstream and Islamist forces that launched an offensive last summer. Only recently have Russia and Syrian forces taken the fight to Islamic State, notably by recapturing Palmyra, the Graeco-Roman city the jihadis overran last year.

The Russian campaign, backed by Iran's Revolutionary Guards and Shi'ite militia such as Lebanon's Hezbollah, has for now outmatched the rebels, including the al Qaeda-linked Nusra Front and units supported by Saudi Arabia, Qatar, Turkey, and the United States.

REBELS LOSE MOMENTUM

Dealing with those groups rather than Islamic State seemed the main aim of Moscow's intervention, analysts say.

"The Russian intervention fundamentally reshaped the Syrian conflict," says Kheder Khaddour from the Carnegie Middle East Center. "The momentum of the rebels does not exist any more."

Putin, diplomats say, weakened the opposition to coax it into accepting a settlement on Russian and Syrian terms. That does not mean the "transitional authority" sought by the U.S. and its allies, but a government expanded to include elements of the opposition, with Assad at its head for the immediate future.

Russia still wants Assad to lead the transition to the elections, while the opposition and its regional allies, including the United States and Europe, insist he should step down. So far no compromises are in sight.

"We need things to advance in the coming weeks. If the political process is just about putting a few opposition people in nominal cabinet posts then this isn't going to go very far," said a European diplomat close to the talks..

"If there isn't a political transition the civil war will continue and Islamic State will benefit from it," he said.

Fawaz Gerges, author of ISIS: A History, said: "At this point the Russians have the upper hand in dictating a solution. The Americans are playing on Russia's playing field."

UNCERTAINTY

His judgment is underlined by Sergei Lavrov, Russia's foreign minister, who boasted in a recent interview that "the Americans understand they can do nothing without Russia. They can no longer solve serious problems on their own".

Yet uncertainty surrounds Moscow's intentions, after Putin suddenly withdrew part of his forces from Syria last month. That led to speculation among Assad's enemies that Russia was contemplating whether to ditch Assad - an outcome many Syria watchers find highly improbable.

"The key issue remains when and if the Russians will act to facilitate this transition. It's unclear, and we get the feeling that the recent talks didn't change much in the Russian position," the European diplomat said.

"I don't think the upcoming round will reach any real decisions on the political process, he added.

Gerges says the partial pull-back sent a message to the Americans that Russia is a rational and credible force that is interested in a diplomatic settlement.

It was also intended as a jolt to Assad, by then so emboldened at the way Russia and Iran had transformed his weak position that he was announcing plans to recapture all of Syria.

"The message to the Assad regime was that Russia doesn't play by Assad's playbook, it doesn't want to get down in Syria's quagmire (but) wants to cut its losses," Gerges believes.

But it is far from clear that Assad interprets these messages the same way.

Last month, he dismissed any notion of a transition from the current structure, as agreed by international powers, calling instead for "national unity" solution with some elements of the opposition joining the present government.

"The transition period must be under the current constitution, and we will move on to the new constitution after the Syrian people vote for it," Assad told Russia's Sputnik news agency.

ASSAD "WILL NOT GO QUIETLY"

Faisal al-Yafai, a leading commentator from the United Arab Emirates, says Russia "played its cards in Syria very cleverly, but miscalculated in one aspect".

"They assumed that once the (Assad) regime felt secure, it would be more willing to negotiate. In fact, the opposite has happened".

"There's a limit to the pressure that Russia can exert on Assad. Assad absolutely will not go quietly -- and certainly not when there is no real alternative to him, even within the regime," says al-Yafai.

Robert Ford, the former U.S. ambassador to Syria and now a senior fellow at the Middle East Institute in Washington, agrees that Russia may not be able to compel Assad to go.

The secret police backbone of Assad's rule remains intact, he says, and "Assad seems confident again, after his much more sober tone last summer. The Russians may have helped him too much, such that Assad can maintain control of key cities and roads for a long time".

Ford also drew attention to the competition over Syria between Russia and Iran, Assad's two main allies. Moscow's emphasis is on its traditional relations with the Syrian military establishment, while Tehran focusses on the militia network it built with Hezbollah to shore up the regime.

"Assad is plenty smart to know how to play one country off against the other. I am not even sure Russia would test its heavy pressure capacity against that of Iran in Damascus. The Russians know they might lose", Ford said.

Russia's involvement in Syria has given it greater insight into the structure of the Assad rule, constructed to intermesh the Assad family and allies from its minority Alawite community with the security services and military command.

ASSAD BUOYANT

Khaddour from Carnegie says Russia now realises the circumstances for a transition do not yet exist, because removing Assad might unravel the whole power structure.

"There is a problem within the regime. It is not capable of producing an alternative to itself internally," says Khaddour, adding the only concession it has made - simply to turn up in Geneva - was the result of Russian pressure.

With limits to Russian and Iranian influence on a newly buoyant Assad, few believe the Geneva talks will bring peace.

"If the Russians felt it was time for a solution they would have reached an understanding with the Americans to give up on Assad without giving up on the Alawites. The circumstances are not ripe yet for a solution," says Sarkis Naoum, a leading commentator on Syria.

The diplomat added: "The fundamental question is still whether the Russians are serious and want this to happen."

"Nobody knows what's in their mind and I'm not sure they even know."

(Additional reporting by John Irish; Editing by Giles Elgood)

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