The Pentagon has confirmed the White House has authorized the early stages of planning for potential military action in Syria. Speaking before a Senate committee, General Martin Dempsey, the chair of the Joint Chiefs of Staff, said military officials have prepared a preliminary “commanders’ estimate” on how a battle would play out for President Obama’s National Security Council. Dempsey outlined some of the military actions the United States could take.

Gen. Martin Dempsey: “Humanitarian relief, no-fly zone, maritime interdiction, humanitarian corridor, and limited aerial strikes, for example. And we’ve—we’re at what I would describe as the 'commanders estimate' level of detail, not detailed planning. Have not been briefed to the President, have been discussed with the President’s national security staff. And as General [James] Mattis testified yesterday, the next step would be to take whatever options we deem to be feasible into the next level of planning.”

Testifying along with Dempsey, Defense Secretary Leon Panetta said the planning is in the preliminary phase and would only get more detailed at President Obama’s request. During the hearing, Panetta was questioned by Republican Senator John McCain, who this week became the first U.S. lawmaker to call for the U.S. bombing of Syria.

Sen. John McCain: “Can you tell us how long, how much longer the killing would have to continue, how many additional civilian lives would have to be lost, in order to convince you that the military measures of this kind that we are proposing, necessary to end the killing and force to leave power? How many more have to die? Ten thousand more? Twenty thousand more? How many more?”

Leon Panetta: “I think the question, as you stated yourself, Senator, is the effort to try to build an international consensus as to what action we do take. That makes the most sense. What doesn’t make sense is to take unilateral action at this point.”