WASHINGTON (AP) -- Top Pentagon leaders are telling Congress the military will be ready if called on to intervene in Syria, but they're setting a high threshold for making such a decision.

Defense Secretary Leon Panetta told the House Armed Services Committee today that the administration has decided that the U.S. will not act unilaterally, and there will be no U.S. "boots on the ground" in Syria.

Panetta and Joint Chiefs chairman Gen. Martin Dempsey insisted that diplomacy remains the best option to force President Bashar Assad to end the crackdown on opponents of his regime. They outlined steps, including sanctions and humanitarian aid, that the U.S. and other countries are taking to pressure the Assad regime after 13 months of bloodshed that the United Nations estimates has left more than 9,000 dead.

Dempsey told the panel the military is working on plans to halt the violence, but Panetta added that the U.S. would get involved militarily only "if there's a consensus in the international community" to do so.

Both Republicans and Democrats on the committee echoed Dempsey's and Panetta's reluctance to use force.