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By Lesley Wroughton and Matt Spetalnick
WASHINGTON, Jan 30 (Reuters) - The United States on Thursday accused Syria of dragging its feet on giving up its chemical arms, putting at risk a deal to remove such weapons of mass destruction from the country as it splits apart in a chaotic civil war.
President Barack Obama this week touted the chemical weapons agreement as one of the few U.S. diplomatic achievements on Syria, but the State Department said just 4 percent of Syria's deadliest chemical agents has been shipped out of the country for destruction at sea.
The United States has few good choices to force President Bashar al-Assad to comply.
A State Department spokeswoman warned that a military option was still possible but urged diplomacy and called on Russia to pressure its ally Damascus to comply with an agreement struck last year to surrender its chemical arsenal.
"The effort to remove chemical agents and key precursor chemicals from Syria has seriously languished and stalled," Robert Mikulak, the U.S. representative to the Organization for the Prohibition of Chemical Weapons (OPCW), told the world's chemicals weapons watchdog in The Hague.
In a blistering statement, Mikulak accused Syria of "open-ended delaying" of the disarmament process.
Assad's decision in September to give up chemical arms helped him avoid threatened U.S. air strikes in retaliation for a poison gas attack near Damascus in August that killed hundreds of people, many of them women and children.
But the international operation to dispose of Syria's chemical stockpile is now six to eight weeks behind schedule and it will miss next week's deadline for sending all toxic agents abroad for destruction, sources familiar with the matter told Reuters.
Delays pose a difficult challenge for Obama, who has faced criticism at home and abroad for failing to do more to quell Syria's nearly 3-year-old civil war.
Obama cited the chemical weapons deal in his annual state of the Union address on Tuesday, saying "American diplomacy, backed by the threat of force, is why Syria's chemical weapons are being eliminated."
U.S. CALL FOR RUSSIAN PRESSURE
Underscoring the Obama's administration's anxiety, U.S. Defense Secretary Chuck Hagel discussed the issue in a call on Wednesday with his Russian counterpart, Defense Minister Sergei Shogun, and asked him to "do what he could to influence the Syrian government to comply."
In a rare case of diplomatic cooperation between the two countries, Moscow and Washington joined forces last year to get Assad to agree to give up his chemical weapons stockpiles.
But critics of Obama say Russia is too close to Syria - its only ally in the Middle East - to enforce the agreement.
U.S. Senator Lindsey Graham, a frequent Republican critic of Obama's Syria policy, said: "Having the Russians disarm Assad is sort of like Mussolini disarming Hitler; I'm not so sure it's going to work."
Though the administration stopped short of threatening action if Syria fails to comply, State Department spokeswoman Jen Psaki said the United States had never taken the military option off the table.
But she insisted diplomacy remained the preferred course and said there was "still the possibility" that Syria would fulfill its pledge to give up its chemical weapons even though, "They are dragging their feet."
After gearing up for and then backing away from military action last year, there seems to be little support in Congress or among the war-weary American public for a new U.S. military entanglement in the Middle East.
Obama's diplomatic engagement with Iran - another Assad ally - is widely seen, at least in part, as driven by his desire to avoid armed conflict over Tehran's nuclear program.
The White House said Syria needs to intensify its efforts to transport chemical weapons to the Mediterranean port of Latakia, from where the material is being shipped out.
"Syria has said that its delay in transporting these chemicals has been caused by 'security concerns' and insisted on additional equipment - armored jackets for shipping containers, electronic countermeasures, and detectors for improvised explosive devices," Mikulak told the OPCW's executive council.
"These demands are without merit, and display a 'bargaining mentality' rather than a security mentality," he added.
MOOD IN CONGRESS
U.S. lawmakers voiced concern about the chemical weapons delays but most did not think it would change the deep reluctance of many members of Congress for more involvement in Syria's civil war, which has claimed more than 100,000 lives.
The Obama administration seized upon the Russian chemical weapons removal proposal last year as it became clear that , amid stiff resistance from both Republicans and Obama's fellow Democrats, Congress would not grant the president the authority to launch military strikes against Assad's forces.
"Unfortunately, most people don't care," said U.S. Senator John McCain, an outspoken advocate of military aid to anti-Assad rebels. "And that's the tragedy of it all."
Dennis Ross, a former Middle East adviser to Obama, said he had always assumed "the Assad regime would have to be coerced every step of the way to destroy its chemical weapons."
"The question will be whether the Russians will tolerate Assad making them look bad," Ross said, suggesting the Syrian president was stalling "to see what he can get away with."
Another option at Obama's disposal would be to push for further sanctions against Syria. But this would have to be supported in the U.N. Security Council by Russia and China, which have so far refused to back such measures against Assad.
Under the deal, Syria has agreed to give up its entire chemical stockpile by mid-2014. Deliveries so far, in two shipments this month to Latakia, totaled 4.1 percent of the roughly 1,300 tonnes of toxic agents reported by Damascus to the OPCW, said the sources familiar with the matter.
Eradicating Syria's stockpile, including sarin, mustard gas and VX, requires massive foreign funding and logistical support. The bulk is to be destroyed on the Cape Ray, a U.S. cargo ship now en route to the Mediterranean. (Additional reporting by Anthony Deutsch in Amsterdam, Jeff Mason aboard Air Force One, Missy Ryan in Warsaw and Patricia Zengerle in Washington; Writing by Matt Spetalnick; Editing by Chizu Nomiyama and Tom Brown)
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