* Syria's problems "none of our business," 65 percent say

* Only 35 percent approve of Obama's handling of crisis

By Gabriel Debenedetti

WASHINGTON, Sept 13 (Reuters) - Three-quarters of Americans support efforts to resolve the crisis in Syria through an international agreement to control chemical weapons, according to a new Reuters/Ipsos poll that shows steady opposition to U.S. military action.

The poll of 776 Americans, conducted over three days this week, indicates that just 25 percent of Americans oppose diplomacy to deal with the crisis that was ignited by the Aug. 21 chemical attack in a Damascus suburb that U.S. officials say killed more than 1,400 adults and children.

The survey reflects the anti-war sentiment that has shadowed President Barack Obama's request for congressional authorization for a military strike against Syrian President Bashar al-Assad's government in light of the chemical attack.

The United States has blamed Assad's government for the attack, while Russia and Assad say it was the work of rebel forces.

An offer by Russia, an ally of Syria, to help put Syria's stock of chemical weapons under international control has raised the possibility of an agreement that could help Obama avoid an embarrassing rejection from a skeptical Congress, or an unpopular military action.

The U.S. Senate, led by Obama's Democrats, has postponed a vote on a military authorization measure while the administration pursues a diplomatic course on Syria. U.S. Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov have been meeting in Geneva. More talks involving the United States, France and Britain are scheduled next week in Paris.

The poll found that Obama's speech to the nation on Tuesday had virtually no effect on Americans' reluctance to engage in Syria's civil war after a decade of U.S. involvement in Iraq and Afghanistan.

In polling of 1,386 Americans conducted Monday through Friday, about 62 percent said the United States should not intervene in Syria, virtually the same percentage as a week earlier.

Reuters/Ipsos pollsters also found that most Americans were not swayed by Obama's argument that the United States had a compelling interest to get involved in Syria to stop the spread of chemical weapons and protect U.S. national security.

About 65 percent of Americans said Syria's problems were "none of our business," the same percentage that said so two weeks earlier.

Only 33 percent of the 776 people surveyed in the three-day poll said that responding to the use of chemical weapons in Syria was "in the national interests of the United States." About 47 percent said it was not.

When it comes to intervention in Syria, public support is "pretty well stabilized right under 1 in 5" Americans, Ipsos pollster Julia Clark said.

OBAMA'S RATINGS DIP

Obama has been criticized by people in both parties for what some have called a muddled policy on Syria. This week's polling suggested the president's approval ratings had taken a hit during the crisis.

Only about 35 percent of Americans said they were satisfied with how Obama and the U.S. government had handled the situation, while 65 percent were dissatisfied. Two weeks ago, 41 percent had been satisfied and 59 percent had been dissatisfied.

Obama's overall approval rating has dipped during the past month as well.

Reuters/Ipsos tracking polls found last Sunday that nearly 57 percent of Americans disapproved of the job Obama had done as president, up from nearly 53 percent on Aug. 18, just before the chemical attack in Syria.

Some analysts say the talks over Syria's chemical weapons are unlikely to succeed, likely leaving Obama - who ran for president as an anti-war candidate - with an increasingly difficult decision on whether to launch a military operation in the face of a reluctant Congress and a disapproving nation.

"This initiative is not going to get very far," said William McCants, director of the Brookings Institution's Project on U.S. Relations with the Islamic World.

"It's going to be very difficult to pull off in a way that will satisfy the Obama administration's desire to ensure that the Assad regime never uses chemical weapons again," McCants added.

The Reuters/Ipsos poll's questions about a possible diplomatic solution to the Syria crisis and on national security interests had a credibility interval, which is similar to a margin of error, of 4.1 percentage points.

The questions about U.S. intervention, whether Syria's problems are the United States' business, and satisfaction with Obama's handling of the situation each had a credibility interval of 3 points. The poll on Obama's overall approval rating also had a credibility interval of 3 points. (Editing by David Lindsey and Peter Cooney)

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