MOSCOW: The Kremlin believes it has taught Washington an object lesson in how to take on Islamist militants in Syria. Basking in the afterglow of Bashar al-Assad's surprise visit to Moscow this week, it now believes it could lead the way diplomatically too.

Russia's actions over Syria, from its decision to launch air strikes to the red carpet welcome it afforded Assad, have irked the White House, which does not want to be seen giving President Vladimir Putin a get out of jail card over the Ukraine crisis.

Yet there is a growing sense in Moscow, and among diplomats and politicians in some countries in the Middle East and the West, that Russia has a better chance than most to combine its increased influence over Assad with its military muscle in Syria's skies to broker a deal to end the Syrian conflict.

"Right now Russia has more chances than any other country to settle this process," said Ivan Konovalov, director of the Center for Strategic Trend Studies in Moscow.

"It cannot do this on its own of course. And Russia cannot control Assad. But it can guide him, make deals with him, and advise him as an ally. It's a massive ask but there is a chance that Russia could pull this off."

Others agree, albeit begrudgingly, seeing Moscow as a flawed interlocutor but one that nonetheless can play a constructive role.

Jamal Khashoggi, the head of a Saudi news channel owned by a Saudi prince, said Moscow is at least a more palatable potential broker for Riyadh than Iran.

"With Iran, it’s an issue of religion, of Shi’ite expansionism," he said. "But for Russia it’s about geopolitics and interests, so we can talk to the Russians," he said.

Russian analysts believe their country's authority as a potential peacemaker had been strengthened by what they see as an effective show of military force in Syria and its repeated refusal to do a deal with the West that would have involved Assad stepping down.

US VACUUM

Western diplomats privately agree there is a window of opportunity for Putin to seize the diplomatic initiative, even if its chances of success are deeply uncertain.

"For me the question is less why is Putin doing this, but more why is he able to do it," said one Western diplomat, who works on the Syria and Iraq crises.

"And here the answer is, whether one likes it or not, because he is filling a void left by U.S. disengagement."

Russian Foreign Minister Sergei Lavrov will try to push Moscow's so far unsuccessful initiative -- of a grand international coalition against the Islamists in Syria -- at a meeting in Vienna on Friday.

US Secretary of State John Kerry will attend as will the foreign ministers of Turkey and Saudi Arabia.

Washington has rejected Moscow's criticism of its policies in the Middle East and reports that Russian strikes have been effective, arguing that they have focused their attacks mainly on Syrian government positions that are most threatened and made little inroads into defeating Islamic State.

"Secretary Kerry will once again reiterate our deep concern about the continued military support for the Assad regime," State Department spokesman John Kirby told reporters this week.

"In our view there’s not going to be a military solution to the civil war, and that any attempt to find one – certainly one that props up Assad – is only going to prolong it and make the threat of extremism deeper in Syria."

Russia expects the meeting to produce "an honest and objective exchange of views about the situation which will give an opportunity to map out a clear path for activating efforts to achieve a comprehensive political resolution,” said Maria Zakharova, a spokeswoman for Russia's foreign ministry.

Yet the idea that Putin, the man the West loves to hate, could eventually emerge as the diplomatic broker-in-chief of the Syria crisis seems risible in many Western capitals and hard to swallow among key regional powers.

The insistence that Assad must immediately step down may have softened somewhat, notably in Washington and Ankara. But it has not gone away, and is at odds with Russia's view that Assad is Syria's legitimate leader.

Saudi Arabia, which is financing some of the militants fighting against Assad, has baulked at Russia's intervention.

Speaking to reporters on the eve of the Vienna meeting, Saudi Foreign Minister Adel al-Jubeir called Russian interference in Syria "very dangerous", accusing Moscow of escalating the conflict, backing a leader with blood on his hands, and of stoking a sectarian conflict.

"There will be no role that he can play other than to leave," the minister said of Assad.

Iran, one of Assad's and now Moscow's staunchest allies, says it is fully satisfied with the Kremlin's approach and that Moscow has kept it fully informed of its initiatives, including the Syrian leader's surprise visit.

"We have supported Russia's measures in Syria. Russia and Iran and the Syrian government have close cooperation," a senior Iranian official told Reuters on condition of anonymity.

REGIONAL SCEPTICISM

But Turkey and Iraq, other key countries in the region, are a far more difficult prospect for Moscow.

Turkey, one of Assad's most vociferous opponents, has been incensed by the Russian intervention, which it says will only prolong the war, and by air space violations by Russian warplanes along its southern border.

Sources in President Tayyip Erdogan's office said the Turkish leader had used a call with Putin on Wednesday to emphasise his concerns about links between the Kurdistan Workers Party (PKK), which has fought a three-decade insurgency against the Turkish state, and militia connected to the Kurdish PYD party in Syria.

Opinion in Iraq meanwhile appears deeply divided. Although some politicians there want Russia to extend its campaign of air strikes to hit Islamist State targets in Iraq, others are fiercely opposed and sceptical of Moscow's aims.

“There is a split between the Sunni and Shi’ite Arabs in regards to Putin. The Sunnis in Iraq agree with their Syrian counterparts in viewing Putin as a murderer who wants to keep Assad in power," Hisham al-Hashimi, an Iraqi security analyst, told Reuters.

Some Shi’ites did favour growing Russian influence, he said, but they were also split and many Iraqis blame Washington for what they say is its own failed intervention.

Russian government officials say the Kremlin is not acting out of affection for Assad or self-interest. Moscow says instead it is trying to contain Islamist militancy before it spreads further afield.

A former Russian diplomat who served in the Middle East also said Moscow was not driven by any attachment to the Syrian president.

He said that Moscow, under Soviet rule, had close relations with then Syrian President Hafez al-Assad, the father of the current Syrian leader but that there had been a cooling of relations when Bashar succeeded his father.

But now, after the strife in Syria, he said Bashar had warmed to Moscow. “He has no choice.”