DAMASCUS, Syria -- International aid to Syrians uprooted by civil war is a "drop in the sea" of what is needed, a top UN official said Monday, estimating that five million Syrians have been displaced inside the country.
In addition, 2 million Syrians have fled to neighboring countries, according to UN figures. The total, of about 7 million, amounts to nearly one-third of Syria's population.
The funding gaps for the displaced remain wide, with donor countries sending less than one-third the money needed to help those displaced, Tarik Kurdi, the representative of the UN refugee agency in Syria, told The Associated Press.
Syria's brutal two-and-a-half-year-old conflict has also claimed more than 100,000 lives, including hundreds who - according to the U.S. - were killed in chemical weapons attacks by the Syrian regime near Damascus on Aug. 21.
Syrian President Bashar Assad's government has denied involvement, instead blaming rebels for the attacks. Neither the U.S. nor the Assad regime has presented proof in public to back up the allegations.
In Washington, President Barack Obama was lobbying Congress to support a military strike to punish the Assad regime for its alleged chemical weapons use. Obama initially seemed poised to launch military action without asking Congress, but over the weekend changed his mind. A vote is expected after Congress returns from summer recess Sept. 7.
On Monday, Obama was to meet with former political rival Sen. John McCain at the White House, hoping the foreign policy hawk will help sell the idea of U.S. military intervention.
On Capitol Hill, senior administration officials briefed lawmakers in private on Sunday to explain why the U.S. was compelled to act against Assad. Further meetings were planned from Monday to Wednesday.
The Arab League, meanwhile, stopped short of endorsing military action. In an emergency meeting in Cairo on Sunday, it called on the United Nations and the international community to take "deterrent" measures under international law to stop the Syrian regime's crimes, but could not agree on whether to back U.S. military strikes.
Two of Assad's most influential foreign backers, China and Russia, lined up against Washington's new attempt to make the case for a military strike.
China is "highly concerned" about possible unilateral military action against Syria and believes the international community must "avoid complicating the Syrian issue and dragging the Middle East down into further disaster," Foreign Ministry spokesman Hong Lei said in Beijing on Monday.
Russian Foreign Minister Sergey Lavrov, meanwhile, dismissed U.S. information given to Moscow on the alleged chemical weapons attack as "absolutely unconvincing."
There was "nothing specific" in the evidence presented by Washington, Lavrov said. "No geographic coordinates, no names, no proof that the tests were carried out by the professionals."
He did not say what tests he was referring to.
Lavrov said U.S. officials told the Russian government they cannot share all the evidence because some of it is classified.
On Sunday, U.S. Secretary of State John Kerry said the U.S. received new physical evidence in the form of blood and hair samples that show sarin gas was used in the Aug. 21 attack.
Kerry said the U.S. must respond with its credibility on the line.
The Syria conflict erupted in March 2011 as an uprising against Assad that quickly transformed into a civil war.
The fighting has displaced 5 million inside Syria, said Kurdi, the UN official. In addition, nearly 2 million Syrians have crossed into neighboring countries, previously released UN figures show.
Before the outbreak of the conflict, Syria had a population of about 23 million people.
Kurdi said the need for aid is far greater than what the international community has provided so far.
"Whatever efforts we have exerted and whatever the UN has provided in humanitarian aid, it is only a drop in the sea of humanitarian needs in Syria," he said. The funding gap "is very, very wide," he added.