US Official Can't Say Syria Chemical Weapons Fully Tracked Down

Assistant Secretary for International Security and Nonproliferation Thomas Countryman (L) listens as Assistant Secretary of State for Near Eastern Affairs Anne Patterson (R) testifies before the Senate Foreign Relations Committee about "Syria after Geneva" on Capitol Hill in Washington, DC, March 26, 2014. Jim Watson/AFP/Getty Images.

During a Senate Foreign Relations Committee hearing on Syria, a State Department official could not confirm that the international community has located Syrian president Bashar al-Assad's entire chemical weapons supply.

Sen. Tim Kaine asked Assistant Secretary for International Security and Nonproliferation Thomas Countryman whether there were any doubts about the thoroughness of Assad's declaration of chemical weapons, all of which are supposed to be destroyed by June 30 as part of a deal brokered by Russia.

"Are there significant questions we have about the extent of the declaration, whether there are undeclared weapons we need to isolate and identify?" he asked.

Countryman could not categorically rule that premise out, saying there was more he could discuss in a classified setting.

"I can only offer to brief you on that in a closed session," he said, adding, "It will be illuminating."

Countryman also told the committee that while Syria has delivered half of its chemical weapons to be destroyed, 65 percent of the most dangerous weapons in the country have yet to be moved out.

"Almost half sounds good," Countryman said as he described the reality behind that figure.

SEE: SYRIA IN PICTURES

Countryman and his colleague, Assistant Secretary of State for Near Eastern Affairs Anne Patterson, acknowledged the Obama administration's Syria strategy has largely fallen far short thus far and that the U.S. is seeking to revise its policy in order to accelerate delivery of nonlethal goods and equipment to the moderate opposition.

"One hundred and fifty thousand people are dead and we are now trying to revise our policy," Sen. John McCain responded in disdain.

In addition to discussing potentially hidden chemical weapons, the officials also insisted on a classified setting to discuss military options that still might be on the table - despite the administration's contention that there is no military solution to the Syria crisis.