A third of the Syrians were displaced either inside or outside the war-torn country, Xinhua quoted UN High Commissioner for Refugees Antonio Guterres as telling reporters.
Among the two million refugees, the first million fled Syria during two years, and the second million fled in six months, which reflected the enormity of the recent escalation of the conflict, he added.
The high commissioner said the situation not only is associated with human sufferings, but also has terrible impacts on the societies and countries that are hosting all the Syrian refugees.
He called for more efforts in massive support for both Syrian refugees and hosting countries.
"Without that massive support, it will be much more difficult to preserve the stability of these countries and to avoid the spillover of this conflict," Guterres said, noting that a UNHCR programme in response to the Syrian refugees crisis is now funded only about 50 percent and other agencies are facing even more difficulties.
"This is a responsibility for the international community that is not only based on solidarity or generosity but it is clearly based on enlightened self-interests," he said.
"If we look at the Syria crisis today, it is more than a national crisis, it became a threat to global peace and security."
The high commissioner said the agency has contingency plans for the increased number of Syrian refugees.
The UNHCR would make "concerted effort in order to better mobilise the international community in support to Syrian refugees and in support to the hosting countries", he said.
--IANS (Posted on 03-09-2013)