The head of the Environmental Protection Agency (EPA) defended big energy infrastructure projects and said Thursday that climate change is not his highest priority.

Speaking to Reuters from his Washington D.C. office, agency chief Andrew Wheeler, a former coal lobbyist, said that concerns about the impact of climate change were overblown under former President Barack Obama’s administration.

Wheeler, unlike President Donald Trump’s first EPA chief, reiterated that he does not dismiss human-caused climate change, or contradict mainstream climate science, however.

“I said before I took this job that I believe in climate change and man has an impact on climate change,” he told Reuters.

But Wheeler did cast doubt on a study released this week by EPA scientists in the journal Nature Climate Change which detailed the urgency of the issue and pressed for early adoption of mitigating strategies.

“Just because our scientists publish something in a journal doesn’t mean that that’s agency policy or all the other scientists at the agency agree with that particular study,” he said.

The measures proposed in the paper, he added, are not EPA policy.

Read More: Here’s What the EPA’s Website Looks Like After a Year of Climate Change Censorship

Wheeler said he believes that water, not climate change, is the number one environmental challenge facing the planet today.

“When you have a thousand children that die a day from lack of drinking water, that’s a crisis and that’s a crisis that we — we collectively as the world — know how to solve that problem,” he said, according to Reuters.

Last year, a landmark U.N. report gave the world 12 years to avert a climate catastrophe and pressed governments to act urgently.

President Trump has sought to boost fossil fuel production in the U.S. and earlier this week issued two executive orders to push states to speed up oil and gas pipeline construction.

Wheeler said the EPA will soon release clarifications and parameters for states to veto energy projects over environmental concerns.

“If the states that are blocking the pipelines were truly concerned about the environment they would look to where [their imported] natural gas would be coming from, and they are forcing the New England states to use Russian-produced natural gas which is not as clean as U.S. natural gas,” Wheeler said. “I think it’s very short-sighted.”

Write to Amy Gunia at amy.gunia@time.com.