The British newspaper said it has learned Gen. David Richards, who heads up Britain's armed forces, met secretly in London a few weeks ago with the military chiefs of France, Turkey, Jordan, Qatar and the United Arab Emirates, as well as a three-star American general to discuss the ways in which the rebels could be supported without boots on the ground. The meeting came at the best of Prime Minister David Cameron, senior Whitehall sources told The Independent.
The newspaper said other U.K. government departments and their counterparts in allied states also have conducted extensive meetings.
Syrian opposition forces have been battling the military of Syrian President Bashar Assad for nearly 22 months. The death toll has reached an estimated 40,000 lives.
Meanwhile, Moscow's position on Assad remains unchanged, despite Russian-U.S. talks seeking to resolve the Syrian crisis, Russia's foreign minister said.
"We are not conducting any negotiations on the fate of Assad," Sergei Lavrov told reporters in Moscow. "All attempts to portray things differently are unscrupulous, even for diplomats of those countries which are known to try to distort the facts in their favor."
The latter comment appeared aimed at Western officials who hinted last week Moscow was ready to help expedite Assad's departure the Los Angeles Times said.
A senior Turkish official told The New York Times a week ago Moscow was "softening" its "political tone" and would look for ways of getting Assad to relinquish power.
Russia has said it is not wedded to Assad, but the official suggested Moscow was now more motivated to find an alternative after Russian President Vladimir Putin acknowledged Assad seemed unwilling to depart.
Putin told reporters in Istanbul, Turkey, after meeting with Turkish Prime Minister Recep Tayyip Erdogan, "We are neither protecting the regime in Syria nor acting as their advocate, but remain worried about Syria's future."
U.S. Deputy Secretary of State William Burns and Russian Deputy Foreign Minister Mikhail Bogdanov met in Geneva, Switzerland, Sunday with U.N.-Arab League Special Envoy on Syria Lakdhar Brahimi.
The three reported no progress afterward, saying in a joint statement the Syria situation was "bad and getting worse." But the statement expressed hope a political solution was "still necessary and still possible."
Syria's civil war spilled over its borders again, this time into the neighboring Lebanese city of Tripoli, where 16 people were killed in fighting between pro- and anti-Assad forces, the state-run Lebanese National News Agency said.
Anger over the killings led to clashes in Tripoli Monday, the news agency reported.
Tripoli is Lebanon's second-largest city.
In Syria itself, rebel and regime forces fought fierce battles in the southern suburbs outside Damascus and near Damascus International Airport, activists said.
The Local Coordination Committees of Syria said 116 people were killed across the country Sunday, including four women and 10 children.
Among the dead were 41 people killed around Damascus, 32 in Aleppo and 22 in Idlib, including seven members of a single family, the coordination committees said.