The United Nations Security Council on Saturday vetoed a draft resolution that would have called for embattled Syrian President Bashar al-Assad to step down, according to the Associated Press.
The resolution was vetoed by Russia and China.
The vote came a day after activists said the Assad government murdered more than 200 protesters in the city of Homs.
Earlier on Saturday, President Obama called on Assad to step aside.
"Assad must halt his campaign of killing and crimes against his own people now," Obama said in a statement. "He must step aside and allow a democratic transition to proceed immediately."