Secretary of State nominee Rex Tillerson said Wednesday he's not prepared based on his knowledge or what's been reported in the public realm to classify Russian President Vladimir Putin a war criminal.



At his confirmation hearing, Tillerson, a former Exxon chairman and CEO, was pressed on the issue by Florida Sen. Marco Rubio, who ran against President-elect Donald Trump for the Republican nomination.



"Is Vladimir Putin a war criminal," Rubio asked Tillerson.



Tillerson responded: "I would not use that term."



Rubio retorted, "Let me describe the situation in Aleppo [Syria], and perhaps that will help you reach that conclusion. In Aleppo, Mr. Putin has directed his military to conduct a devastating campaign."

"He's targeted schools, markets, not just assisting the Syrians in doing it. His military has targeted schools and markets and other civilian infrastructure that resulted in the death of thousands of civilians," Rubio added.

Aleppo has been a hotbed of the terror group Islamic State, or ISIS.

"I understand there's a body of record in the public domain. I'm sure there's a body of record in the classified domain," Tillerson said. "Those are very, very serious charges to make. I would want much more information before reaching a conclusion."

Tennessee Sen. Bob Corker, chairman of the Senate Foreign Relations Committee where the hearing was being conducted, asked Tillerson if he were able to confirm through U.S. intelligence agencies the types of actions Rubio described, "you would agree, that those, in fact, would be war crimes, right?"

Tillerson responded, "Yes, sir."

Russia's stated purpose in Syria is to fight ISIS. The U.S. and its allies have also been waging bombing efforts against the militants, while trying to diplomatically edge out of power Syrian leader Bashar Assad, an ally of Moscow.



The extensive questioning of Tillerson about Russia was expected due to his business dealings with Russia and his perceived close ties to Putin.