“Their sorrow about the suffering of the Syrian people is nothing more than crocodile tears,” it said.
GCC states Saudi Arabia and Qatar are among the leading champions of the rebels.
Russian Foreign Minister Sergei Lavrov, the al-Assad regime’s most powerful ally, said in Iran that all “responsible countries” had to act to ensure the Geneva II conference achieves a positive outcome.
Meanwhile, an online forum that often features statements from jihadists urged the Islamic State of Iraq and the Levant (ISIL) to free two Spanish journalists kidnapped in September in Syria.
The Syrian Observatory for Human Rights said on Wednesday ISIL had evicted 15 Kurdish families from their homes in Tal Abyad, in Raqa Province northeast of the capital.
It also said 13 regime loyalists were killed battling rebels at Adra in Damascus Province, and that five civilians also lost their lives.
An estimated 126,000 people have been killed in the conflict, which began in March 2011.