Syria's seat at the Arab League will remain vacant until the opposition completes the formation of its institutions, the pan-Arab group's secretary general Nabil al-Arabi said on Sunday.
"The last Arab summit in Doha in March 2012 adopted the principle of granting Syria's seat within the League to the opposition, but it has not yet established its institutions and must take further steps in this regard," Arabi said after a meeting of the Arab Ministerial Council.
The fierce repression of the anti-regime uprising that began in March 2011 resulted in Damascus being suspended from the Arab League in late 2011.
Last November, Syrian National Coalition chief Ahmad Jarba said the opposition was claiming his country's seat in the organisation.
The Istanbul-based Coalition -- which includes several opposition groups -- is considered to be one of the most important representatives of the Syrian opposition.
But it has yet to present a united front, and is struggling to impose its legitimacy on the ground.
Nevertheless, Sunday's League ministerial meeting invited Jarba to speak at its next meeting scheduled for Kuwait on March 25.
Nearly three years ago, on March 15 2011, peaceful protests began against President Bashar al-Assad's regime.
These later turned into an armed uprising after the government engaged in a brutal crackdown on dissent.
According to Britain-based monitoring group the Syrian Observatory for Human Rights, more than 140,000 people have been killed since the conflict began.