Joe Biden under pressure from left on climate change

Former US vice president and 2020 Democratic presidential hopeful Joe Biden has faced pressure from freshman congresswoman Alexandria Ocasio-Cortez, who criticized politicians who seek a "middle of the road" approach on climate change policy speaks during the First State Democratic Dinner in Dover, Delaware. and A file photo taken on February 27, 2019 US Congresswoman Alexandria Ocasio-Cortez (D-NY) listens as Michael Cohen, attorney for President Trump, testifies before the House Oversight and Reform Committee in the Rayburn House Office Building on Capitol Hill in Washington, DC. (AFP Photo/SAUL LOEB, MANDEL NGAN) (AFP/File)

Washington (AFP) - Democratic 2020 frontrunner Joe Biden was forced into defending his environmental record Tuesday after a popular progressive in Congress demanded presidential hopefuls abandon a "middle-of-the-road" approach to combatting climate change.

"You never heard me say middle of the road. I've never been middle of the road on the environment," the former vice president, 76, said at a campaign stop in New Hampshire, a day after first-term congresswoman Alexandria Ocasio-Cortez implicitly rebuked Biden over the issue.

The 29-year-old House Democrat bemoaned lawmaker inaction 30 years ago -- when Biden served in the Senate -- as US space agency NASA warned them about the existential threat of climate change.

"I will be damned if the same politicians who refused to act then are going to try to come back today and say we need a 'middle of the road' approach to save our lives," she said.

Ocasio-Cortez, a rising liberal voice in her party, was speaking at an event promoting the Green New Deal, an ambitious strategy she backs that calls for zeroing out greenhouse gas emissions within a decade.

Biden said nobody has been more consistent on environmental issues than he has, pointing to several policies to combat climate change that were implemented during the eight-year Obama presidency.

"Tell her to check the statements that I made and look at my record," he said.

The veteran Democrat said Monday that critics were "peddling" a Reuters article that cites two sources close to the campaign as saying Biden will take the "middle ground" with a climate policy that appeals to environmentalists as well as working-class voters who elected President Donald Trump.

Biden said he would be laying out a detailed climate policy this month, and insisted he was a leader in the climate change battle.

But his comments suggested a pragmatism contrasting with the bold approach of Ocasio-Cortez's Green New Deal.

"We do need to finish this green revolution in a way that's rational, and we can do it and afford it and get it done now," Biden said.

Some 2020 rivals seized on the spat, including liberal Senator Bernie Sanders, who tweeted last week that "there is no 'middle ground' when it comes to climate policy."