WASHINGTON – President Donald Trump should "admit that climate change is real" and start figuring out ways to confront it.

That wasn't advice from prominent congressional Democrats Nancy Pelosi, Chuck Schumer or Alexandria Ocasio-Cortez but rather from one of the president's staunchest allies in Congress: Republican Sen. Lindsey Graham of South Carolina.

"I'm tired of playing defense on the environment," Graham told reporters on Capitol Hill Wednesday as he and other GOP lawmakers announced the formation of the Roosevelt Conservation Caucus, which will "embrace and promote constructive efforts to resolve conservation and environmental problems."

In response to a question about the president's environmental record, Graham said Trump should agree with the overwhelming scientific consensus that the planet is warming and come up with an aggressive response.

"I would encourage the president to look at the science, admit that climate change is real and come up with solutions that do not destroy the economy like the Green New Deal," the senator said, referring to the plan progressive Democrats have promoted to halt climate change. "We will win the solution debate. But the only way you're going to win that debate is to admit you've got a problem."

Trump often mocks the science behind climate change and once referred to it as a "hoax" perpetrated by the Chinese to gain competitive advantage. He has instructed his administration to expand the development of carbon-emitting fossil fuels that contribute to a hotter planet. And he has rolled back previous efforts to reduce carbon emissions, including the Clean Power Plan that was a signature of President Barack Obama's efforts to confront the growing crisis.

In a White House news conference Monday defending his environmental record, Trump's only mention of climate change was when he said he "withdrew the United States from the unfair, ineffective, and very, very expensive Paris Climate Accord."

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The pact that called for countries to meet voluntary emissions reduction goals was signed by nearly 200 nations, including the U.S. in 2016 when Obama was president.

Frustrated with the administration's continuing push to expand fossil fuels, Sen. Bernie Sanders, Ocasio-Cortez and other progressive lawmakers earlier this week called on Congress to declare a "climate emergency," a largely symbolic effort designed to spur action on global warming.

"This is a moral imperative," Sanders, I-Vt., a top-tier contender for the 2020 Democratic presidential nomination, told reporters on a phone call Tuesday. "There is no choice. We are going to have to take on the greed of the fossil fuel industry and the ignorance of Donald Trump and transform our energy system in a very bold way."