The U.S.' chief military officer said on Wednesday that he was cautious of recommending armed intervention in Syria, expressing concern that ill-conceived action could turn the country into a failed state.
"Before I would recommend a military solution ... I would have to be convinced that the aftermath of the military option would not lead to a failed state in which the suffering would actually be worse," Army General Martin Dempsey, the chairman of the Joint Chiefs of Staff, told reporters at an air force base in Poland.
Dempsey added that political leaders should consider other options along with miltary action.
In a letter released on Monday, Dempsey outlined five options the U.S. military was prepared to undertake, from providing training to establishing no-fly zones or conducting limited attacks on military targets.
In the letter, Dempsey warned involvement in Syria would be an act of war that could cost billions of dollars.
The U.S. military currently delivers humanitarian aid, provides security assistance to Syria's neighbours and non-lethal help to the Syrian opposition.
The White House said in June it would provide military aid to the rebels after concluding that Assad's forces had used chemical weapons.