KUWAIT CITY (AP) — International donors committed $3.8 billion in aid for Syrians affected by the grinding civil war at a donors' conference in Kuwait on Tuesday, less than half of what the United Nations requested in its largest appeal yet for the country.

More than a quarter of the total came from two countries: Kuwait, which hosted the third annual conference and pledged half a billion dollars, and the United States, which promised the largest single commitment of $507 billion.

The European Commission and EU member states pledged close to $1.2 billion total, double the overall EU pledge at last year's conference.

The U.N. had requested $8.4 billion this year — its largest appeal yet for the war-ravaged country.

The civil war, now in its fifth year, has killed at least 220,000 people. Around 11 million people, or half of Syria's population, have been displaced, according to U.N. figures. Of the displaced, nearly 4 million have been forced to flee to the nearby countries of Lebanon, Turkey, Jordan, Iraq and Egypt, stretching the resources of those nations.

U.N. Secretary General Ban Ki-moon said the money pledged would help Syria's neighbors overcome the strain of hosting millions of refugees as he announced the total amount pledged during the one-day conference in the opulent Bayan Palace.

Earlier in the day, he offered stinging remarks, saying Syrians are the victims of the "worst humanitarian crisis of our time," and that he has "only shame and deep anger and frustration at the international community's impotence to stop the war."

"They are not asking for sympathy, they are asking for help," he said of the Syrian people.

Syria, long one of the most stable countries in the region, was swept up in Arab Spring protests in 2011 calling for greater freedoms, better standards of living and more political rights. Protests quickly spiraled into armed conflict as President Bashar Assad's forces unleashed a lethal crackdown on cities where protests erupted. The conflict has since escalated into a proxy war between Arab Gulf monarchies backing some rebel groups and Iran backing Assad. A U.S.-led coalition is now bombing Islamic State group targets in both Syria and Iraq.

The U.N. Office for the Coordination of Humanitarian Affairs says the Syrian war has created "the largest displacement crisis in the world" and that 12.2 million people — just under half of them children — are in "dire need of aid."

The U.N. High Commissioner for Refugees António Guterres said the situation for people is "at a tipping point" and "unsustainable." Guterres said this current U.N. appeal is different from previous ones because it recognizes both the immediate and the longer-term imperatives of responding to the crisis.

The U.N. says $2.9 billion is needed in 2015 for Syrians inside the country and $5.5 billion for those who have fled to the five surrounding countries.

Prior to the conference, UNRWA, the U.N. agency that works with Palestinian refugees, said that just four percent of its emergency work for those affected by the Syrian war had been funded for the year. Due to high unemployment caused by the Syrian civil war, more than 95 percent of the 535,000 Palestinian refugees from Syria rely on UNRWA assistance, particularly cash distributions to individuals that last year totaled just $16 a month.

U.S. Ambassador to the U.N. Samantha Power said that despite the U.N. making its largest humanitarian appeal in history, "many countries are giving the same amount, or even less than they have in the past." Tuesday's roughly half-billion-dollar U.S. pledge is in addition to nearly $3.2 billion the country has provided since the conflict began, she said.

"Years from now, when Syrians and the world look back on the country's horrific crisis, they will remember which countries stepped up to help people in dire need, and which countries did little or nothing at all," she told the conference.

Some 78 countries and 40 international aid organizations were present at this year's conference.

Ahead of this year's gathering, the German government said it would pledge $277 million in new aid — part of the EU's overall figure. Kuwaiti state media say local charities and aid organizations pledged another $506 million just before the conference started.

Gulf envoys addressing the conference said the United Arab Emirates pledged $100 million. Saudi Arabia pledged $60 million, while Norway said it would pay $93 million and the United Kingdom $150 million.

At last year's donors' conference, about $2.4 billion was pledged, though the U.N. had called for $6.5 billion. In 2013, some $1.5 billion was pledged, less than half the U.N.'s appeal for $4.4 billion.

The U.N. humanitarian office's Financial Tracking Service said in November that nearly a quarter of last year's pledges, or $585 million, had not been fulfilled.

In his speech at the Kuwait conference, the U.N. secretary general said that more of last year's pledges have since come through, totaling 90 percent of total promises made.