Tillerson Calls Climate Change a 'Risk,' Breaks With Trump on Paris Agreement

— -- Rex Tillerson, former CEO of the ExxonMobil Corporation and President-elect Donald Trump’s nominee for secretary of state, was confronted about Exxon’s climate change record by Sen. Tim Kaine (D-Virginia) during Senate confirmation hearings.

Kaine questioned Tillerson about reports claiming Exxon purposefully obscured scientific findings on climate change and attempted to spin the public on scientific conclusions that carbon dioxide emitted from fossil fuels has a negative effect on the environment.

Tillerson sidestepped answering Kaine’s questions--telling Kaine he no longer works for Exxon and the questions should be directed at the corporation. But Kaine pressed him.

“And let me ask you do you lack the knowledge to answer my question or are you refusing to answer my question?” Kaine said.

“A little of both,” said Tillerson.

In a statement in 2015, an Exxon rep told Scientific American, "We didn’t reach those conclusions, nor did we try to bury it like they suggest,” referencing a report at the time in Inside Climate News.

Throughout his confirmation hearing, Tillerson was pressed about his positions on climate change and his 41-year history of working for the largest oil and gas corporation in the world. Protesters interrupted the hearing multiple times to shout their concerns about Trump, the environment, and Tillerson’s connection to Exxon.

But during his confirmation hearing, Tillerson broke with Trump on the most influential international effort to combat global warming, the Paris climate change agreement, with which the president-elect disagrees.

Tillerson implied that he supports the treaty, ratified by Obama in 2015, which commits 180 countries, including the United States and China, to meeting specific emissions-reduction goals.

“As I indicated, having a seat at the table to address this issue at a global basis and I think it’s important, better served by being at that table than leaving that table,” said Tillerson.

Trump has said he would “cancel” the Paris agreement but after the election told the New York Times in an interview that he was reconsidering his hardline stance against it. “I’m looking at it very closely,” Trump said. “I have an open mind to it.”

Tillerson explained during the hearing that Trump has invited his views on climate change and Trump is aware that his position is on the public record, a position Sen. Bob Corker (R-TN) pushed Tillerson to define.

“I came to my personal position [on climate change] over about 20 years as an engineer and a scientist, understanding the evolution of the science,” said Tillerson. “I came to the conclusion a few years ago that the risk of climate change does exist and that the consequences of it could be serious enough that actions should be taken.”

But Tillerson was vague when asked whether he believes human activity is linked to climate change.

“The increase in the greenhouse gas concentrations in the atmosphere are having an effect,” said Tillerson. “Our ability to predict that effect is very limited.”

In a statement, environmental organization the Sierra Club called Tillerson's answers on climate change "as murky as water after an oil spill by his former employer."

"At a time when our climate continually puts families and communities at risk, his refusal to acknowledge that fossil fuels -- which Exxon profits from -- are harming the climate is reckless and dangerous."

ABC News' MaryAlice Parks contributed to this report.