Marco Rubio Mum on Whether He Will Support Tillerson for Secretary of State After Human Rights Questions

Tillerson's nomination to be Secretary of State may face it's first roadblock.

“I think it’s important, if you stand for moral clarity, that you be clear,” Rubio told reporters outside the hearing. "I'm prepared to do what's right."

Rubio’s comments could signal the first major roadblock for a Trump cabinet nomination.

"I mean, it's clear that I'm concerned about some of his answers and encouraged by a few others," Rubio told reporters. "But obviously I want to go back and think through this a little bit."

“If we're going to have moral clarity in our foreign policy, we have to be clear,” said Rubio. “And I don't want to see us move towards a foreign policy where human rights only matters when nothing else matters, when something more important isn't standing in the way.”

Rubio’s committee vote could impact whether Tillerson’s nomination proceeds to a full vote on the Senate floor. Rubio placed his hesitancy on the importance of the secretary of state role as the face of the United States around the world.

“He's been nominated to what I believe is the second most important post in the executive branch,” said Rubio. “And so I intend to take this very seriously.”

ABC News' Mary Bruce and Ali Rogin contributed to this report.<