It's no secret that Saudi Arabia wants to topple Syrian President Bashar al-Assad.



But just how much Riyadh is willing to use its money to reach that goal can be surprising.



One measure was a meeting on July 31 in Moscow between Saudi intelligence chief Prince Bandar bin Sultan and Russian President Vladimir Putin.



Details of the meeting are still sketchy, but Syrian opposition sources close to Saudi Arabia say the prince offered to buy up to $15 billion of Russian weapons if Moscow agreed to ease its support of Assad and stop blocking future UN Security Council resolutions on Syria.



At the same time, the prince reportedly offered to ensure that no Persian Gulf country would export natural gas across the Arabian Peninsula to challenge Russia's position as the main gas supplier to Europe.



Moscow appears to have not been interested, with the Kremlin saying on August 9 that media accounts of an offer were inaccurate.



Putin's foreign-policy adviser, Yury Ushakov, told reporters that "Putin did not discuss a deal." He added that "no specific questions on developing military cooperation were discussed" and that the meeting was of "a philosophical character" only.



Taking The Lead



Still, however detailed the offer was -- or not -- the Saudi intelligence chief's visit leaves no doubt that Riyadh now regards the Syrian conflict as a top foreign-policy priority.



"Since about June-July this year, they have taken the lead in funding the Syrian opposition and also deciding to an extent who is leading the Syrian opposition, to putting more and more money for arms, and probably also arms, into the arsenal or coffers of the Syrian opposition, and also to become more diplomatically active, both in the West and in Russia," says Volker Perthes of the German Institute for International and Security Affairs in Berlin.



What is driving Saudi Arabia, Perthes says, is fear. "It fears, probably in descending order, that Iran may win, or Iran may establish hegemony in the Middle East and in the Levant, build a land bridge from Iran proper thorough Iraq and Syria to Lebanon," he says.



"It fears that Hizballah would win in Lebanon against Sunni politicians whom Saudi Arabia has been supporting for ages, and it fears that Assad could prevail or, if the opposition wins, that it is the wrong part of the opposition that wins."



But Riyadh has other concerns, too.



Among them is the danger the Syrian conflict will destabilize Jordan, where King Abdullah II faces a determined domestic opposition movement at the same time the country struggles to cope with hundreds of thousands of Syrian refugees.



"If the Kingdom of Jordan seemed to be in trouble, the Saudis would rush in to try to protect it as the Saudis rushed into Bahrain," says Theodore Karasik of the Dubai-based Institute for Near East and Gulf Military Analysis. "From their point of view the collapse of a monarchy would be a huge disaster, with intense geopolitical ramifications for other monarchies."



Wider Divisions



Underneath all these worries runs yet another: the Syrian conflict is increasingly attracting sectarian extremists from neighboring states and beyond. That, Karasik says, risks exacerbating sectarian tensions across the region.



"Those groups that are affiliated with Al-Qaeda and those groups that are affiliated with and backed by Iran and Hizballah also have violent confrontations with each other at this time, so it is not only at a state level but it's also at a nonstate level between various militias and groups," the analyst says.



Riyadh faces two dangers from Saudi militants who may one day come home from Syria. One is that returning Sunni fighters could strengthen Al-Qaeda's long-running war against the Saudi royal house. The other is that returning Shi'ite fighters could help radicalize the kingdom's historically underprivileged Shi'ite minority in the country's oil-rich east.



As Saudi Arabia assumes the lead in backing Syria's rebels, it remains unclear how much room it sees for compromise with other world powers with stakes in the conflict.



But Jane Kinninmont, a regional expert with London-based Chatham House, notes the reports of last week's meeting suggest Riyadh is increasingly ready to explore a wide range of possibilities, even with powers that currently are firmly lined up on the opposing side.



"One of the things that's interesting about the recent reports of their engagement in Russia is that this would be a case of them using a carrot and not only the stick," Kinninmont says. "There has been a lot of Saudi pressure on Russia. We have seen Russian business delegations to Saudi Arabia canceled because the Saudis have not wanted to meet with them. We have seen a great deal of anti-Russian rhetoric coming out of Saudi clerics. But there hasn't been much in the way of going to the Russians and saying, 'What do you want and can we do some kind of deal.'"



The Syrian conflict, which began with demonstrations against Assad in March 2011, is now almost 2 1/2 years old. According to the latest UN figures, more than 100,000 people have died in the conflict.