* Lavrov says draft resolution on aid "one-sided"
* Diplomats say vote on draft unlikely this week
* U.S. supports resolution on humanitarian aid in Syria (Adds Security Council meeting, comments from Russian and French envoys)
By Louis Charbonneau and Gabriela Baczynska
UNITED NATIONS/MOSCOW, Feb 11 (Reuters) - The U.N. Security Council on Tuesday began debating a Western-Arab draft resolution that would demand humanitarian aid access to besieged areas in conflict-torn Syria, a text Russia has dismissed as "detached from reality."
The text was prepared by Australia, Luxembourg and Jordan, whose envoys presented their draft resolution meant to increase aid to Syria to the full 15-nation Security Council.
Last week the countries had submitted it to the council's five permanent, veto-wielding members, including Russia, but Moscow swiftly rebuked the proposal as a non-starter.
"We had a good exchange on the challenges of the humanitarian situation," Russian U.N. Ambassador Vitaly Churkin told reporters after the meeting, without giving details.
French Ambassador Gerard Araud told reporters that Churkin told the council Moscow was prepared to work on some kind of resolution on aid, but not the present draft. He also said it was unclear when the council would vote on the text, adding that negotiations have only just begun.
Several diplomats said a vote was unlikely before next week given Russia's dismissive initial reaction and concerns about upsetting fragile peace talks between the Syrian government and opposition, which resumed this week in Geneva.
"It's a text, very simple," Araud said. "It's not political. It's balanced. There's no reason to oppose it. It can be amended."
He added that France did not want a "provocative text," suggesting Paris was prepared to accommodate some of Russia's objections in negotiations on the text to avoid a veto.
Since the war began in 2011, Russia and China have vetoed three Security Council resolutions condemning Syrian President Bashar al-Assad's government and threatening it with sanctions. Moscow has suggested that it is ready to use its veto power again.
"The ideas (on the text) they shared with us were absolutely one-sided and detached from reality," the Interfax news agency quoted Russian Foreign Minister Sergei Lavrov as saying after talks with Algerian Foreign Minister Ramtane Lamamra.
Russia's Churkin has gone further, predicting on Monday that the draft would fail. "This text is not going to be adopted, let me tell you," he said.
HUMANITARIAN CRISIS IN HOMS
But the U.S. Ambassador to the United Nations Samantha Power said Washington strongly supports the idea of such a resolution.
"The Security Council needs to speak with one voice," she said in a statement. "Every day the council remains silent, we let down the Syrian people, and we fail to uphold our role as guardians of international peace and security."
The war has killed more than 130,000 Syrians and driven a third of the country's population from their homes.
The opposition Syrian National Coalition urged the council to adopt the resolution, saying in a statement that the Security Council should adopt "measures ensuring the immediate stoppage of violence and access of aid to all those in need in Syria."
Rupert Colville, spokesman for the U.N. human rights office in Geneva, said Syria's government had broken its obligations under international law, which require states to ensure minimum food supplies, essential medicine and safe water.
"Almost none of these obligations have been met in Old Homs and various other besieged areas in recent months," he said.
The Syrian government and opposition have agreed on a humanitarian pause to allow the delivery of aid to Homs, Syria's third-largest city, and the evacuation of civilians, though aid workers came under attack over the weekend.
The draft resolution condemns rights abuses by Syrian authorities and armed groups, and demands that the government stop all aerial bombardment of cities and towns as well as the indiscriminate use of bombs, rockets and related weaponry. It also condemns "increased terrorist attacks," and calls for the withdrawal of all foreign fighters from Syria.
The draft expresses an intent to impose sanctions on individuals and entities obstructing aid and if certain demands in the resolution are not met within 15 days of its adoption.
Asked if U.N. human rights chief Navi Pillay thought it was time for a Security Council resolution to force the Syrian government to meet its obligations, Colville said: "We certainly wouldn't object to actions by the Security Council."
U.N. aid chief Valerie Amos has repeatedly called on the council to use its influence to improve the dire humanitarian situation in Syria, though she has stopped short of demanding a legally binding resolution.
Lavrov said Russia would be ready to consider a draft only if it was "not about one-sided accusations aimed at the regime." He called on the Security Council to agree on a resolution condemning "terrorist activity" in Syria.
Assad's government describes all of those fighting to oust him as terrorists and has pushed for efforts to combat "terrorism" to be the main focus of the peace talks in Geneva. (Additional reporting by Michelle Nichols, writing by Louis Charbonneau and Gabriela Baczynska; editing by Steve Gutterman, Raissa Kasolowsky, Mohammad Zargham and G Crosse)