WASHINGTON (AFP) - US President Barack Obama on Thursday (Sept 24) accepted an invitation to meet Russian counterpart Vladimir Putin, as a drive to revive efforts to resolve the Syrian conflict kicked into higher gear.
The announcement that Putin and Obama will hold talks at the United Nations in New York on Monday comes amid an apparent shift on Syrian President Bashar al-Assad's potential role in any deal to end the four-year war that has killed 250,000 people.
And US Defense Secretary Ashton Carter said Moscow and Washington could finds ways to cooperate in the crisis.
Turkish President Recep Tayyip Erdogan, a fierce Assad critic, suggested for the first time that the Syrian president could play a part in a future political transition.
But "nobody envisages a future with Assad in Syria," Mr Erdogan cautioned.
In a sign that European thinking may also be changing, German Chancellor Angela Merkel said "we have to speak with many actors, this includes Assad, but others as well." Russia, a longstanding Assad ally, has rankled the West by building up its military presence in Syria.
On Thursday, it sparked fresh alarm by announcing it would carry out naval exercises in the eastern Mediterranean this month and in October.
'Gasoline on the fire'
At the Pentagon, Carter said if Russia were to fight Islamic State jihadists while also pursuing a political solution, and not just "indiscriminately" attack Assad foes, the United States and Moscow might find ways of working together.
"On a course like that, it is possible that we could find areas of cooperation," Carter said.
"But if it's a matter of pouring gasoline on the fire on the civil war in Syria, that is certainly not productive." French Defence Minister Jean-Yves Le Drian called on Moscow to justify its "very significant" buildup in Syria and said if its intention was "to protect" Assad, it should say so.
European leaders, faced with the worst migrant crisis since World War II, have called for a "renewed UN-led international effort" to end a war that has forced 12 million people from their homes.
The tensions over Syria have further strained ties between Russia and the West which have plunged to Cold War lows over the Ukraine crisis.
However, while the two sides have spent months trading barbs over the Syria conflict, the flood of refugees on Europe's doorstep and the jihadist threat posed by the Islamic State group have given new urgency to ending the chaos.
The foreign ministers of France, Britain and Germany - as well as EU foreign affairs chief Federica Mogherini - held discussions on Syria in Paris on Thursday.
Germany's Frank-Walter Steinmeier said as he arrived that it was too early to raise the question of whether Assad should be involved in peace talks.
"There is a need to stop the fighting in the region," Steinmeier said.
"Therefore we have to find an approach... to bridge the different positions of the actors in the region. Tonight we are preparing our common European position." NATO Secretary-General Jens Stoltenberg urged Russia to make its intentions in Syria clear - and said they should assist in US-led strikes on Islamic State extremists.
"The first step now is to sit down with the United States and to make clear what are (Russia's) intentions... and to try to cooperate and give a constructive contribution to the efforts led by the United States to fight ISIL (Islamic State)," he told AFP.
Syrian officials have said Russia is already helping their fight against Islamic State, which has seized large parts of its territory.
The Syrian military for the first time on Wednesday deployed drones supplied by Russia in its fight against the jihadists, a security source in Damascus said.
Syrian ambassador to Russia Riad Haddad told Interfax news agency that Moscow's assistance would help Syria "finally win against terrorist groups."
But experts warn that significant obstacles remain to any solution to the brutal Syrian conflict with major players in the West and the Gulf on the one hand, and Russia and Iran on the other, pursuing vastly different military and diplomatic tactics.
Western leaders have long demanded Assad's departure as part of any diplomatic solution, while Russia and Iran want him to stay.
US Secretary of State John Kerry said last week the US was prepared to "negotiate" with Assad on the conditions of his exit and urged Russia to persuade Assad to enter talks.
"What we want is a political transition away from him and towards a government that is responsive to the Syrian people," State Department spokesman John Kirby said Thursday.
But a German government source warned Merkel's comments in Brussels late Wednesday signalled "nothing new" as representatives of Assad's regime had often joined negotiations.