GCC Secretary-General Abdulatif al-Zayani said in a statement on November 12 that the nations of the oil-rich bloc will give support to the Syrian National Coalition to "realize the aspirations of the Syrian people."
The GCC comprises Saudi Arabia, Bahrain, the United Arab Emirates, Oman, Qatar, and Kuwait.
The Arab League later recognized the group as the "legitimate representative" of Syria's opposition.
Meeting in Cairo late on November 12, Arab League foreign ministers called on other groups that oppose Syrian President Bashar al-Assad to join the coalition.
An array of groups opposed to Assad's government agreed on November 11 to form a new, broader coalition following four days of talks in Qatar.
The agreement was welcomed by the United States and a number of Western states.
Russia urged the new body to negotiate with the Assad regime and to reject outside interference.