The great tragedy of this century’: More than 2 million refugees forced out of Syria

Syrian refugees urge US action as millions flee 1:46

More than 2 million Syrians have poured into neighboring countries as refugees, the United Nations revealed on Tuesday.

Around 5,000 people per day are fleeing the three-year conflict, which the U.N. says has already claimed over 100,000 lives. 

United Nations High Commissioner for Refugees special envoy Angelina Jolie, right, speaks with Syrian refugees in a Jordanian military camp in June. Olivier Laban-Mattei / UNHCR via AP, file

“Syria has become the great tragedy of this century -- a disgraceful humanitarian calamity with suffering and displacement unparalleled in recent history,” said António Guterres, the U.N.’s high commissioner responsible for refugees.

The crisis has dramatically worsened in recent months, according to the U.N.'s refugee agency. 

"There has been a massive escalation of arrivals in 2013," the U.N.'s Office for the Coordination of Humanitarian Affairs (UNHCR). "Over one million Syrian refugees have registered as refugees since the beginning of 2013."

Meanwhile, U.N. special envoy for refugees and Hollywood star Angelina Jolie warned that world leaders risk being “dangerously complacent” over the Syria crisis.

UN: Syrian refugees exceed 2 million 2:31

She said some of Syria's neighboring countries "could be brought to the point of collapse."

"The world is tragically disunited on how to end the Syria conflict,” the actress said in a statement. "The world risks being dangerously complacent about the Syrian humanitarian disaster."

"The tide of human suffering unleashed by the conflict has catastrophic implications," she added in comments timed to coincide with the new UNHCR figures

“There should be no disagreement over the need to alleviate human suffering, and no doubt of the world's responsibility to do more,” she said. “We have to support the millions of innocent people ripped from their homes, and increase the ability of neighboring countries to cope with the influx."

More than 97 percent of those leaving are hosted by countries in the immediate surrounding region, in countries such as Iraq, Egypt and Turkey.

McCain: Obama 'put himself in a difficult situation' 3:38

Ministers from Iraq, Jordan, Lebanon, and Turkey will meet with UNHCR in Geneva on Wednesday to discuss the pressure that the refugee exodus is placing on them.

A further 4.25 million people are displaced inside Syria, according to the latest data, which taken together with those seeking refugee status amounts to more than six million people who have been displaced from their homes.

The figures come as the U.S. and its allies lay the diplomatic and political groundwork for strikes on Syria in response to an alleged chemical weapons attack by the regime of President Bashar Assad.

On Monday, the White House ratcheted up lobbying to convince Congress to authorize military action against Syria. President Barack Obama met with Senators John McCain (R-Ariz.) and Lindsey Graham (R-S.C.) Monday afternoon for the first of a string of meetings this week laying the groundwork for congressional approval.

This follows Secretary of State John Kerry telling NBC's Meet The Press on Sunday that samples collected from the site of the chemical weapons attack have tested positive for the nerve agent sarin, which is used in chemical warfare.