As thousands of Syrian protesters poured onto the streets after midday prayers Friday, the European Union announced a ban on oil imports that could strip away a major source of financial support for the government's five-month-old crackdown on dissent.
At least 12 protesters were killed on Friday, activists said, as Syrian security forces surrounded mosques during prayers, restricting demonstrations, carrying out arrests and in some cases shooting at worshippers who chanted, "Death rather than humiliation."
Activists and European governments hope that the ban on purchasing Syrian oil - the toughest action the European Union has yet taken against president Bashar al-Assad's government - will make it harder to fund the effort against the protesters.
"These oil sanctions will hit the regime in the heart," said Wissam Tarif, a human rights activist with the global advocacy group Avaaz.
"The state has made sure that ordinary Syrian citizens would feel the effects of the uprising. But we haven't seen the regime so far signaling" that it was feeling an economic pinch itself, he said.
The United States had already banned Syrian oil imports, but that move was largely symbolic. Europe buys most of Syria's oil, spending $4.1 billion - or more than $11 million a day - in the country in 2010, according to European Commission figures.
Syria's economy is not transparent, but analysts estimate that before the protests started in March, oil exports accounted for 20 to 30 percent of the government's income. Since then, with other economic sectors struggling, oil exports have become even more important.
As concern has mounted that Assad is showing no signs of relenting, the international community has become more willing to put direct pressure on his government, and activists based in the country have increased their requests for intervention. In mid-August, the United States and the European Union said that Assad needed to step down.
"President Assad is carrying out massacres in his own country," Polish foreign minister Radoslaw Sikorski said on Friday in Sopot, Poland, where he and his European counterparts were meeting to discuss a response to Syria. Analysts estimate that Syria exports just over a quarter of the roughly 400,000 barrels of oil it produces every day. Because of its oil's consistency - heavy and difficult to refine - finding other purchasers will be challenging, if not impossible, they said.
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