(CNN) -- (CNN) -- U.N. Secretary-General Ban Ki-moon expressed disappointment Wednesday that Russia and China this week blocked a Security Council resolution against a crackdown in Syria, and Turkey called the move "unfortunate."
Ban said he regretted the Security Council's failure to agree on the resolution, which called for an immediate halt to the crackdown against opponents of Syrian President Bashar al-Assad.
Ban said the level of violence in Syria is "unacceptable" and "can't go on like this," a spokesman said. Ban said he hopes the Security Council can overcome its divisions.
Turkey, which shares a border with Syria, said the Tuesday veto by Russia and China will not stop it from taking further action. Turkish Prime Minister Recep Tayyip Erdogan promised Wednesday to implement a "package of sanctions."
But exactly what form additional sanctions might take -- on top of the arms embargo on Syria already imposed by Ankara -- is not yet clear.
International powers are seeking a halt to the violent repression of pro-reform protests in the Middle Eastern country. The nearly seven-month-long offensive has drawn world condemnation.
Shashank Joshi, an associate fellow at the Royal United Services Institute in London, told CNN the U.N. resolution would have been "extremely useful" in increasing pressure on al-Assad through the imposition of measures that everyone would have to observe.
In the absence of the resolution, he said, Turkey is now the principal option for putting pressure on Syria.
"The country with the most influence in all this is probably Turkey," said Joshi, also a doctoral student at Harvard University. "It's eager to appear as if it is against Assad, but it's also moving cautiously because it may have to work with him if he clings on."
Trade sanctions, Joshi said, would be "extremely important" as they might peel away support for the regime from those in the country with money.
Turkey could also do more to help the opposition within Syria, send more humanitarian aid over the two countries' porous border, and expand its sanctions against targeted individuals, he said.
Making the Syrian economic elite, based mostly in Damascus and Aleppo, feel the squeeze of sanctions is key, said Bahadir Dincer, a Middle East expert at the Ankara-based International Strategic Research Association think tank.
"They have to feel that if they continue to support the regime, their interests will be harmed," he said. "This is very important, critical -- if they change their position, if they act with the opposition groups in the street, then the (al-Assad) regime will be in a difficult position."
But, he said, the effect of sanctions is lessened if Syria can still trade with Russia and China -- and the U.N. Security Council resolution veto has left Turkey more isolated in terms of taking action against Syria.
Turkish foreign ministry spokesman Selcuk Unal told CNN via text message that Turkey will continue to monitor the situation in Syria.
Dincer said he believes Turkey may now need to look for partners in the Arab world, perhaps Saudi Arabia, in order to keep up pressure on Syria and combat the al-Assad regime's efforts to muddy the waters by claiming it is fighting armed groups on the streets.
Shadi Hamid, director of research at the Brookings Doha Center, told CNN the Security Council veto sent a message to the Syrian government that it still has allies -- such as Russia, China, Iran and Hezbollah -- and "gives them a sense that they can wait this out."
Demonstrators have until now been protesting peacefully. But any civil violence is likely to draw in regional players like Iran and Hezbollah, Hamid said, which could make the situation "very messy."
"That's why the international community has to feel this sense of urgency, because as bad as it is now, it's probably going to get worse," he warned.
The United States, the European Union and Canada have so far taken a lead in implementing measures on an individual basis.
In seven rounds of sanctions, the European Union has barred imports of Syrian oil and investments in the Syrian oil sector, as well as banning the delivery of Syrian bank notes and coinage produced in the EU to the Syrian Central Bank. It has also placed people and entities it considers responsible for supporting "repression" in Syria under a travel ban and an asset freeze.
American authorities have frozen Syrian government assets in the United States, barred Americans from making new investments in Syria and prohibited any U.S. transactions relating to Syrian petroleum products, among other things.
Canada expanded its existing sanctions Tuesday, imposing travel restrictions and an asset freeze on more regime members and supporters, as well as barring the buying, shipping and import of Syrian gasoline and banning new investment in its oil industry.
But China said Wednesday the U.N. Security Council resolution it vetoed would not have helped "ease Syria's situation." Ma Zhaoxu, a spokesman for China's foreign ministry, said the draft resolution would have "put pressure blindly on Syria."
The Russian ambassador to the United Nations said the Security Council action would have been "an intervention" that would have sent the wrong message to the international community.
The statements from Moscow and Beijing failed to convince those frustrated in their determination to back efforts to pressure Syria through the United Nations.
U.S. Ambassador Susan Rice said Tuesday that the United States is "outraged" at the veto. Leaders from France, Germany, Portugal and Britain also expressed disappointment in the move.
Joshi said he believes Moscow and Beijing were motivated by a combination of factors, among them a distrust of interference by the international community and anger from Russia over the way the NATO resolution on action to protect civilians in Libya has been interpreted.
Also at play are "more grubby commercial interests," he said, with Syria an important customer for Russian arms and a provider of oil to China.
The international community is unlikely to come back to the Security Council unless circumstances change significantly inside Syria, he said, especially given the stubbornness of Russia's opposition to a resolution that had already been watered down to meet its demands.
Meanwhile, another round of violence flared in Syria Tuesday as reports of more deaths surfaced amid the relentless government crackdown on protesters.
CNN's Ivan Watson, Richard Roth, Arwa Damon and Mick Krever contributed to this report.