UN Secretary-General Ban Ki-moon attends a high-level meeting on Syria at the Security Council Chamber at the UN Headquarters in New York, Sept 21, 2016. [Photo/Xinhua]

UNITED NATIONS - UN Secretary-General Ban Ki-moon on Wednesday called on the UN Security Council to fully support his special envoy in working on convening formal talks to resolve the Syria conflict.

"We are at a make or break moment" in Syria, where the civil war broke out in March 2011, Ban told an open council meeting on Syria.

He also called for the council support for his special envoy for Syria, Staffan de Mistura, in his efforts to develop proposals for future talks, or risk destroying the international community's credibility in being able to uphold "our common humanity."

The Security Council now has "no higher responsibility" than backing political path in Syria, Ban said.

The council meeting was held on the sidelines of the annual high-level debate of the UN General Assembly, the week-long event which opened here Tuesday.

"We are at a make or break moment," Ban said. "I challenge everyone to use their influence now to restore a cessation of hostilities, enable humanitarian assistance everywhere it is needed, and support the United Nations in charting a political path for the Syrians to negotiate a way out of the hell in which they are trapped."

"You have now no higher responsibility in your service as members of the United Nations Security Council," Ban said.

As a result of the longstanding conflict, more than 300,000 Syrians have been killed, half of the Middle East country's population has been uprooted, and much of its infrastructure lies in ruins, he noted.

In addition, many Syrians fear that fragmentation of their country could follow, with Daesh (also known as the Islamic State) and al-Qaida affiliates poised to exploit further chaos, he said.

"The Syrian tragedy shames us all," he said. "The collective failure of the international community should haunt every member of this Council."