world: U.N. announces $1.5 billion in aid for Syrian refugees

Syrian refugees at the Bab al_Salama Camp in Syria on December 7.NEW: At least 161 people killed across Syria Wednesday, according to rebel groupUnited Nations: A quarter of Syria's population needs food, water, shelter, medical careThe U.N. is seeking more than $520 million in additional aid saying things are likely to worseSyria has been in the midst of war since March 2011 that pits rebels against al-Assad's forces

(CNN) -- The United Nations has launched humanitarian plans worth $1.5 billion to help ease the suffering of millions of Syrians both inside and outside the country.

More than 525,000 Syrians have already crossed into neighboring countries, the United Nations announced Wednesday, and it estimated that more than a million will flee in the next six months.

The body believes that a quarter of Syria's population needs food, shelter, medical attention, hygiene materials, clothes and other relief after enduring nearly two years of war.

Read more: Syrian VP calls for 'historic settlement,' national unity government

The United Nations is also asking for more than $520 million in additional aid, anticipating that the situation will only get worse in 2013.

That amount, officials believe, will help contribute to aid for an estimated 4 million people inside Syria who urgently need help. The number of residents suffering has quadrupled from 1 million in March 2012 to 4 million in December, the United Nations reported Wednesday.

A child sits in the back of a vehicle at the border crossing leading to Masnaa, Lebanon, as people wait to stamp their documents before leaving Syria on Wednesday, December 19. Click through to view images from Syria from December, or see photos of the conflict from November.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":true,"x":7,"y":2,"pos":1,"title":"Showdown in Syria"}

Palestinian children who fled the Syrian refugee camp of Yarmuk wait at the Masnaa Border Crossing leading into Lebanon on December 19.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":2,"title":"Showdown in Syria"}

Syrians line up outside a bakery offering cheap bread in Aleppo, Syria on Sunday, December 16. cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":3,"title":"Showdown in Syria"}

A Syrian boy walks past a rebel fighter in the northern town of Darkush, Syria, on Friday, December 14.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":4,"title":"Showdown in Syria"}

Two men on a motorcycle lead a horse through the northern town of Darkush, Syria, on December 14, 2012.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":5,"title":"Showdown in Syria"}

Rebel fighters push out a boat carrying two Syrian women fleeing to Turkey through the Orontes River near the northern Syrian town of Darkush on December 14.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":6,"title":"Showdown in Syria"}

Passengers gather at a terminal at the airport in Aleppo, Syria, on Wednesday, December 12.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":7,"title":"Showdown in Syria"}

A member of the Syrian opposition's Al-Buraq Brigade stands guard on a main road in the northern Syrian town of Ain Dakna near the Turkish border on Monday, December 10. Click through to view images of the fighting from December, or see photos of the conflict from November.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":8,"title":"Showdown in Syria"}

A Free Syrian Army fighter takes position as he aims his weapon in Aleppo's al-Amereya district on Tuesday, December 11.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":9,"title":"Showdown in Syria"}

Men warm themselves by a fire on a street corner in Aleppo, Syria, on Sunday, December 9.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":10,"title":"Showdown in Syria"}

A rebel soldier watches Al-Jazeera news in a shop near the front lines in Aleppo on December 9.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":11,"title":"Showdown in Syria"}

A rebel soldier prays in a shop in Aleppo on December 9.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":12,"title":"Showdown in Syria"}

Syrians mourn a fallen fighter at a rebel base in the al-Fardos area of Aleppo on Saturday, December 8.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":13,"title":"Showdown in Syria"}

A Syria rebel commander sits behind a desk in his bombed-out position in Aleppo on December 8.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":14,"title":"Showdown in Syria"}

A Syrian rebel fighter emerges from a hole in a wall in Aleppo on December 8.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":15,"title":"Showdown in Syria"}

Rebel fighters take part in a demonstration against the Syrian regime after Friday prayers in Aleppo on December 7.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":16,"title":"Showdown in Syria"}

A wounded rebel fighter is transported to a hospital in the back of a truck in Aleppo, Syria, on Thursday, December 6. At least 23 people died in Syria on Thursday, most of them in Damascus and Aleppo, according to the opposition Local Coordination Committees of Syria. cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":17,"title":"Showdown in Syria"}

Rebel soldiers stand guard inside a building in Aleppo on December 6. cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":18,"title":"Showdown in Syria"}

Angelina Jolie, special envoy for the U.N. refugee agency, meets with Syrian refugees at the Zaatari refugee camp outside Mafraq, Jordan, on December 6. cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":19,"title":"Showdown in Syria"}

In this handout from the Shaam News Network, Free Syrian Army fighters stand guard against forces loyal to Syrian President Bashar al-Assad in the Al-khalidiya neighborhood of Homs on Tuesday, December 4. cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":20,"title":"Showdown in Syria"}

In this handout from the Shaam News Network, Free Syrian Army fighters take cover in destroyed buildings during clashes with regime forces on December 4.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":21,"title":"Showdown in Syria"}

Syrians cross the border from Ras al-Ain, Syria, to the Turkish border town of Ceylanpinar on Tuesday, December 4. cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":22,"title":"Showdown in Syria"}

Boys walk through a damaged area In Aleppo, Syria, seen through a destroyed car on December 4.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":23,"title":"Showdown in Syria"}

A man inspects rubble in a neighborhood of Aleppo on Sunday, December 2.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":24,"title":"Showdown in Syria"}

The bodies of three children reportedly killed in a mortar shell attack are laid out for relatives to identify at a makeshift hospital in Aleppo on December 2. cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":25,"title":"Showdown in Syria"}

Smoke rises from fighting in the Hanano and Bustan al-Basha districts of Aleppo on Saturday, December 1. cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":26,"title":"Showdown in Syria"}

Syrian-Kurdish women and members of the Popular Protection Units, an armed opposition group to the Syrian government, stand guard during a comrade's funeral in a northern Syrian border village on December 1.cnnArticleGallery.currentImageList[cnnArticleGallery.currentImageList.length] = {"currentPicture":false,"x":7,"y":2,"pos":27,"title":"Showdown in Syria"}

Photos: Showdown in Syria Event.observe(window, 'load', function() {//report the first gallery image to ADBPif(typeof(cnn_adbptrackpgalimg) == 'function' && typeof(cnnArticleGallery) != 'undefined') {cnn_adbptrackpgalimg(cnnArticleGallery.currentImageList[0].image, "");}});Many have fled. Between 2,000 and 3,000 refugees are crossing into Turkey, Jordan, Lebanon and Iraq every day, according to the United Nations.

Plans to help Syria have changed much over the past several months, which is "indicative of the rapid developments on the ground and the dramatically deteriorating humanitarian situation in the country," said Radhouane Nouicer, the regional humanitarian coordinator for Syria with the United Nations. "The magnitude of this humanitarian crisis is indisputable."

Read more: Refugee figures fail to give true picture of Syria crisis

The aid announcement comes on the same day that one of the United Nations' outreach groups told reporters that about 100,000 Palestinians have fled a large refugee camp in the Syrian capital of Damascus due to government airstrikes and fighting there.

By daybreak Wednesday, 1,092 refugees from the Yarmouk camp had crossed into Lebanon through the Masnaa border crossing, seeking refuge with relatives in Palestinian camps in Bekaa, Sidon and Beirut.

Yamouk camp spokesman Abu Mohammed, who supports the Free Syrian Army's cause of unseating President Bashar al-Assad, told CNN that the Palestinian people at the camp are not fighting in the war.

"The camp was supposed to be a safe haven," he said. "This was created as a safe zone for refugees. No one can find anywhere else to go."

He said non-stop shelling on the Yarmouk camp has forced tens of thousands to flee, but Mohammed estimates 100,000 remain. "You have 100,000 people trapped under mortar shelling surrounded by a large Syrian Army presence. This could be a true massacre," he said.

He called on the international community for help.

But a Palestinian politician whose group is believed to support Assad said the Free Syrian Army and its affiliates are responsible for injecting the refugees into the conflict.

"The Yarmouk camp was safe business as usual until the last few weeks, when the FSA started shelling the camp from outside," said Hussam Arafat, of the Popular Front for the Liberation of Palestine General Command. "They were clashing and firing mortars on the Syrian army, which was based on the outskirts of the camp ... Then they managed to control the camp after a bloody battle with the Syrian army."

Life is dangerous even for the elite in Syria these days. Interior Minister Mohammed Shaar was admitted to the American University Hospital in Beirut on Wednesday for treatment for injuries sustained when his ministry building was bombed last week, the official Lebanese news agency NNA reported Wednesday.

"Minister Shaar is in a stable condition, sustaining burns and shrapnel and will not need surgery... He needs observation and treatment," one of the doctors who treated Shaar told NNA.

Other Wednesday developments

At least 161 people were killed across Syria Wednesday, according to the Local Coordination Committees of Syria, a Syria-based opposition activist network. Of those deaths, 67 occurred in Damascus and its suburbs, and 50 occurred in Aleppo.

At least 40 people were killed and dozens were wounded by a car bomb that exploded in Aleppo's Marjeh neighborhood, the LCC said.

The Damascus suburb of Deir Al-Asafir endured fierce shelling from rocket launchers, according to the LCC.

The FSA downed a war plane in Hama, the LCC said

In Homs, Assad's forces raided university residences near Shamas village and arrested students, the LCC said.

CNN's Ivan Watson in Istanbul, Salma Abdelaziz in Atlanta, and Kareem Khadder in Jerusalem contributed to this report.

December 5, 2012 -- Updated 1232 GMT (2032 HKT)

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