European Union (EU) foreign policy chief Catherine Ashton on Thursday said the EU will continue to support the peacefully political transition in Syria, after UN-Arab League Joint Special Envoy to Syria Kofi Annan announced his resignation.

Ashton said in a statement that she was "deep regret" at the resignation of Annan, who was appointed to the role on Feb. 23 to find a solution to the crisis in Syria.

"The EU continues to support the efforts of the UN and the Arab League, and calls for the early appointment of a successor to carry on Mr. Annan's work towards a peaceful political transition in Syria," she said.

"The Six Point Plan remains the best hope for the people of Syria, and any further militarisation of the conflict by any of the parties can only bring greater suffering to Syria, its citizens, and the region as a whole."

Ashton said "Annan's resignation makes clear how unfortunate it has been that the UN Security Council was unable to agree to a resolution, which would have endorsed the communique of the Action Group and so helped compliance with the Six Point Plan."

She said that the EU remains committed to pursuing a Syrian-led political transition to the crisis that would meet the democratic aspirations of the Syrian people and bring back stability to Syria.

UN Secretary-General Ban Ki-moon announced on Thursday that Annan had informed him and Arab League Secretary-General Nabil Elaraby of his intention not to renew his mandate when it expired on Aug. 31.