WASHINGTON – Former Secretary of State John Kerry blasted Republicans and President Donald Trump during congressional testimony on Tuesday, saying that freshman Rep. Alexandria Ocasio-Cortez had shown more leadership than the president has in his life when it comes to the issue of climate change.

Kerry, a former Democratic senator who served as a cabinet member in the Obama administration, praised Ocasio-Cortez while appearing before the House Oversight Committee to testify about climate change and national security. He was asked by Republican Rep. James Comer about funding for the Green New Deal, a climate change proposal brought forward by Ocasio-Cortez, D-N.Y., and Sen. Ed Markey, D-Mass. It was defeated in the Senate last month.

"My focus is on how we're going to move forward and you know, we all have some differences with one piece of legislation or another but in proposing what she has proposed together with Sen Markey, Congressman Ocasio-Cortez has in fact offered more leadership in one day or in one week than President Trump has in his lifetime on this subject," Kerry said.

He pointed out there are a variety of ideas on how to combat climate change but added, "I don't know that any of them are coming from your party or your side of the aisle. Do you have a plan to deal with climate change?"

Kerry argued that Ocasio-Cortez's proposal helped get people "talking about" climate change and questioned why Republicans weren't more concerned with the issue before now.

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"Did you have any hearings on it the last couple of years? Mostly on Benjazzi, if I recall when I was up here," Kerry said, referencing the list of investigations pertaining to the 2012 attack on the U.S. diplomatic compound in Benghazi, Libya. "So, I think what we ought to do is stop the politics and get down to really serving the people."

After listening to GOP lawmakers slam the Green New Deal proposal during Tuesday's hearing, Ocasio-Cortez suggested the plan's detractors should end their "fixation" on what they've heard about the non-binding blueprint and familiarize themselves with the Green New Deal by reading it.

"We don't need cliff notes for a 14-page resolution that was designed to be read in plain English by the American people," Ocasio-Cortez said she, looking over to the Republican side of the dais. "So I would encourage my colleagues to actually read the resolution presented so they can speak to it responsibly and respectfully."

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She said if the U.S. doesn't act to prevent climate change from worsening, "we will have blood on our hands."

Her Green New Deal proposal called not only for combating climate change by eliminating carbon emissions caused by fossil fuels and shifting the economy to one powered by renewable fuels but also prescribes a broad platform supporting free housing, medical coverage and higher education for all Americans.

GOP senators ridiculed the plan because the Green New Deal's original talking points called for even further-reaching goals: a build-out of high-speed rail that would make carbon-emitting airplane travel obsolete; an end to dependence of nuclear power as well as fossil fuels; and the creation of "a sustainable, pollution and greenhouse gas free, food system" that would no longer rely on "farting cows."

A self-described Democratic socialist, Ocasio-Cortez has become a target of Republicans, who have propped her up as a leader within the Democratic Party and a symbol of the party's future.

During a rally last week for Trump, "AOC sucks!" chants broke out when the president's eldest son, Don Jr., mentioned Ocasio-Cortez and the Green New Deal.

The president has repeatedly referenced Ocasio-Cortez, 29, during rallies and other speaking events, saying the proposal was "done by a young bartender." He said other Democrats were "petrified of her," and suggested her progressive ideas could help him and Republicans win in 2020.