Story highlights 'It's a shame for us to lose our leadership position,' said Christine Todd Whitman, EPA administrator under George W. Bush

'The EPA can't survive with 31% cuts to the budget,' Whitman said

(CNN) On this day last year, the Paris Agreement, aimed at reducing greenhouse gas emissions and preventing global warming, was opened for signatures, eventually going into effect in November.

This week, President Donald Trump was to meet with senior administration officials to discuss the deal -- and whether the United States should withdraw from it.

The meeting was postponed indefinitely, and with key Trump advisers divided over the issue, it is still uncertain what Trump will finally do about the accord. But advocates of greater federal regulations to address climate change are already expressing dismay about the administration's stance.

It's no secret that Trump has called climate change a "hoax" in the past. Last month, he signed an executive order rolling back Obama-era climate regulations, which will initiate a review of the Clean Power Plan, an effort to cut carbon dioxide emissions that Obama started.

And Trump's pick to run the Environmental Protection Agency, Scott Pruitt, has made it clear addressing climate change will not be an urgent priority for the agency under his watch, declining to say after his confirmation whether he would forbid EPA scientists from studying the human connection to the issue.

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