WASHINGTON – A day after Senate Republicans short-circuited the Green New Deal, House Speaker Nancy Pelosi unveiled a significantly more modest approach Wednesday to addressing climate change: to block the Trump administration from abandoning the international accord known as the Paris Agreement.

Calling climate change "the existential threat of our time," Pelosi described the Climate Action Now Act as "only Step 1" of Democratic efforts to confront global warming.

The move is far less ambitious than the Green New Deal, the sweeping proposal from Rep. Alexandria Ocasio-Cortez, D-N.Y., that calls for shifting completely from fossil fuels to renewable energy in the coming years and prescribes a broad social justice platform that includes free housing, medical coverage and higher education for all Americans.

A number of Democrats, including Pelosi, had signaled for weeks that they weren't ready to get behind such an ambitious plan that had no chance of getting passed in a GOP-controlled Senate or being signed by President Donald Trump, who has openly mocked the science behind climate change.

In unveiling the bill Wednesday, House Democrats tried to reclaim the narrative in Washington after several days of Republican victories, including special counsel Robert Mueller's finding that the Trump campaign did not collude with the Russian government to interfere in the 2016 U.S. election.

The Democrats' climate change bill seeks to force the U.S. back into the Paris Agreement, in which nearly 200 countries in 2015 committed to keeping global temperatures no more than 2 degrees Celsius above pre-industrial levels.

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Though the agreement imposes no penalty for nations that miss the carbon emissions levels they set for themselves, they are required to monitor, report and periodically reassess those targets.

Trump has often touted his decision to leave the Paris Agreement in 2017 as a move to boost the American economy, especially manufacturing and energy jobs. Democrats, environmental groups and some economists counter that the growth of green jobs would more than make up for jobs lost in the fossil fuel industry.

Also Wednesday, Senate Democrats planned to unveil a Special Committee on Climate Change as a way to keep the issue alive after Tuesday's defeat of the Green New Deal.