President Barack Obama said he does not foresee a scenario in which he would send US ground troops to Syria and outlined a deliberate approach to determining whether the Syrian government had used chemical weapons in a two-year civil war.
Obama insisted that the United States has not ruled out any options in dealing with Syria as the United States investigates whether the government of Syrian President Bashar al-Assad used chemical weapons.
But Obama, who has spent much of his presidency winding down wars in Iraq and Afghanistan, made clear he was not inclined to send troops to Syria, saying "I do not foresee" such a scenario.Leaders in the region that he has consulted on this issue agree with him, Obama said.
If Syria is found to have used chemical weapons, however, Obama will be under pressure to take some action beyond what the United States is already doing. The Obama administration is considering sending lethal aid to Syrian rebels.
Obama, who has come under fire from some critics in Washington who contend he has a muddled approach to Syria, insisted the United States is not standing by even as it waits for a chemical weapons ruling.
"We're not waiting," he said. "We are working to apply every pressure point that we can on Syria."
The United States has said it has "varying degrees of confidence" that chemical weapons have been used by Syria's government, which violates a "red line" that Obama had established against such action.
At his news conference with Costa Rican President Laura Chinchilla, Obama said more evidence is bound to turn up if Syria is continuing to use chemical weapons.