Syria refugees
Syrian refugees warm themselves by a fire at a refugee camp in Atimeh, on the Syrian-Turkish border of  Idlib Governorate Monday, Dec. 10, 2012. Reuters/Abdalghne Karoof

The top U.N. refugee agency announced on Tuesday that the number of Syrians registered as refugees or awaiting registration has topped 500,000, and the numbers are climbing by an estimated 3,000 a day. The number could pass 700,000 by the end of 2012, UNHCR estimated.

Speaking to reporters in Geneva, UNHCR spokeswoman Melissa Fleming said that only 40 percent of the registered refugees in the region are actually living in refugee camps. Meanwhile, in Lebanon and even parts of North Africa, there are no refugee camps for the more than 166,000 Syrian refugees living there. In such cases, people will rent homes, live with host families, or take shelter in "collective centers" -- mosques, churches, schools, or whatever is available.

The U.N. estimates at least 20,000 people have been killed since the beginning of the conflict in March 2011. Between 1 million and 2 million Syrians are still in the country and in need of humanitarian aid.

“The numbers of those struggling to live on the local economy and who eventually come forward to register are expected to increase as the conflict in Syria continues, resources are depleted and host communities and families can no longer support them,” Fleming said.

Of particular concern to aid organizations and the refugees are the winter conditions many people now must endure.

"Syrian refugees arriving during recent bad weather, reached Jordan with soaked clothing and mud-covered shoes due to heavy rainfall," Fleming told reporters. "UNHCR protection teams described the night time arrivals as fearful, freezing, and without proper winter clothing."

UNHCR said they have now distributed 112,000 thermal blankets in the Za'atri camp in Jordan, one of the largest refugee camps, where Angelina Jolie made a second visit last week in her capacity as U.N. Special Envoy. The camp also received a batch of gas heaters from the Norwegian Refugee Council.

The World Food Programme is also on the scene in Jordan, Lebanon, Turkey and Iraq, attempting to provide at least one meal to every family in the camp. Inside Syria, they are attempting to reach the more than 1.5 million displaced people for monthly food assistance, but the WFP said in a statement that bread shortages and higher food prices mean food insecurity is on the rise.

While refugees flee and Syrian President Bashar al-Assad gears up for what looks to be a last stand, with or without chemical weapons, the U.S. State Department announced on Tuesday that it has designated the al-Nusra Front as a foreign terrorist organization. Al-Nusrah is a known collaborator with the Free Syrian Army fighting against the Assad regime, but the State Department said that al-Nusrah is also an alias for al-Qaeda in Syria.

"Since November 2011, al-Nusrah Front has claimed nearly 600 attacks – ranging from more than 40 suicide attacks to small arms and improvised explosive device operations – in major city centers including Damascus, Aleppo and Homs," State Department spokeswoman Victoria Nuland said in a statement.

"Through these attacks, al-Nusrah has sought to portray itself as part of the legitimate Syrian opposition while it is, in fact, an attempt by AQI [al-Qaeda in Iraq] to hijack the struggles of the Syrian people for its own malign purposes."

Nuland added that the U.S. has provided $50 million in "nonlethal assistance" and $200 million in humanitarian aid to the Syrian opposition.

"The violent, sectarian vision of al-Nusrah is at odds with the aspirations of the Syrian people, including the overwhelming majority of the Syrian opposition, who seek a free, democratic and inclusive Syria," Nuland said. "Extremism and terrorist ideology have no place in a post-Assad Syria."

This designation could complicate any end-game of the war and transition efforts. Analysts say many factions of the Free Syrian Army are merely hired guns. The U.S. estimates that al-Nusrah fighters make up 9 percent of the FSA, and claims that the designation is meant to marginalize extremists, and to strengthen, not weaken, opposition efforts.

"We want to put the opposition on notice that these guys are becoming more of an issue and they need to do something about them," an anonymous U.S. official told CNN.

On Monday, the EU met with Syrian opposition political leaders in Brussels and officially recognized the opposition as "the legitimate representatives of the Syrian people," they said in a statement. The EU joins France and the UK in recognizing the Syrian National Coalition as Syria's legitimate government. The European Commission also announced it would provide another $39 million in aid to Syrians affected by the conflict, bringing the total to $210 million, Al-Jazeera reported.

The German Foreign Ministry also announced on Monday that they had expelled four members of the Syrian embassy in Berlin, in an attempt to further "reduce dealings" with the Assad regime, they said in a statement. The Syrian ambassador to Germany was expelled in May.

Meanwhile in Syria, rebels took full control of a military school near Aleppo, killing 35 government troops, Al-Jazeera said.