EXCLUSIVE: The head of the Republican Study Committee (RSC) has called on Treasury Secretary Janet Yellen to launch an investigation into whether Russia secretly funded U.S. green groups that advocate against domestic oil and gas production. 

Rep. Jim Banks, R-Ind., led a letter to Yellen Friday that cites a 2015 Washington Free Beacon report that suggested the California-based Sea Change Foundation may allegedly be a conduit for Russian oil interests in funneling money to groups like the League of Conservation Voters (LCV), the Natural Resources Defense Council (NRDC), the Sierra Club and the Center for American Progress. 

Rep. Jim Banks, R-Ind., is chair of the Republican Study Committee. 

"Russia spent millions promoting anti-energy policies and politicians in the U.S.," Banks said in a statement to Fox News Digital. "Now, thanks to Biden’s war on domestic energy, U.S. oil production has dropped 10%, pushing up prices and enriching and emboldening Putin before he invaded Ukraine."

HOUSE REPUBLICANS DEMAND ANSWERS FROM ENVIRONMENTAL GROUPS OVER ALLEGATION OF COLLUSION WITH RUSSIA

Banks continued: "Unlike the Russia hoax, Putin’s malign influence on our energy sector is real and deserves further investigation."

The Treasury Department did not immediately reply to email requests for comment on whether it would investigate. 

Banks' letter coincides with a similar effort from House Energy and Commerce Committee Republicans who are calling on certain environmental groups to disclose their ties to a non-governmental organization which is, according to the committee, reportedly used by Russian President Vladimir Putin to make an impact on American energy production.

GAS PRICES FUELING COMING DEMOCRATIC BLOODBATH IN MIDTERMS, REPUBLICANS SAY

Three environmental groups – the League of Conservation Voters (LCV), the Natural Resources Defense Council (NRDC), and the Sierra Club – reportedly have ties to the San Francisco-based NGO environmental organization called the Sea Change Foundation, according to Republicans on the committee.

In a letter sent to each of the three groups, Republicans inquired about the funding the groups have received from Sea Change since 2006 and called for disclosure of whether the groups "are aware of concerns that Sea Change may be a conduit for Russian funding."

U.S. Treasury Secretary Janet Yellen speaks during a news conference with Irish Finance Minister Paschal Donohoe at Government buildings in Dublin, Ireland, Nov. 1, 2021. REUTERS/Clodagh Kilcoyne (REUTERS/Clodagh Kilcoyne)

The Center for American Progress said the allegations have been "thoroughly debunked," citing a 2018 article in which Sea Change founders Nat Simons and Laura Baxter-Simons say they have received no funding from outside sources and the foundation's $500 million in grants for climate and clean energy were based on their family money.

"In the midst of a serious national security crisis, this is a disgusting disinformation campaign by unpatriotic Republican extremists who have been actively cheering on Putin throughout the Trump years, and who are now masking that disgrace with lies that have been thoroughly debunked," Center for American Progress said in a statement to Fox News Digital.

Sea Change told Fox News Digital that it has no connection to Russia or Russian funds and wants to put to rest the allegations. A statement from co-Founders and co-Directors, Nat Simons and Laura Baxter-Simons, restates their 2018 position. 

"All funding to Klein (now Sea Change Foundation International) has been exclusively from philanthropic contributions by Bermuda-based family trusts of which, I [Nat Simons], my children, and family-related philanthropic organizations are the only beneficiaries," the statement said. "I wish to clarify that press reports speculating that Klein has received funding from outside sources are factually incorrect and have no basis. Neither Klein nor Sea Change Foundation has ever solicited or accepted contributions from non-family related sources."

Similarly, LCV, NRDC and Sierra Club have pushed back hard against these GOP allegations in previous statements to Fox News Digital. 

The NRDC said the "allegations are false" and are "rooted in a smear campaign."

"We receive no funding from the governments of Russia or China," Bob Deans, the director of strategic engagement for the NRDC, said. "We answer to our independent leadership, and we don’t do the bidding of any government – foreign or otherwise – in our work to advocate for commonsense environmental protections in the public interest. These allegations are rooted in a smear campaign orchestrated nearly a decade ago by fossil fuel interests and a right-wing think tank. They only serve then, as now, as a distraction."

A statement provided to Fox News from the LCV said the "story is completely false and has been put to rest for years."

"We have no connections to Russia, or China, and have been an effective advocate for environmental protection for over 50 years," the group stated. "These false and poorly researched allegations are rooted in a nearly 10-year-old right-wing think tank and fossil fuel industry-funded smear campaign that gets revived every few years to serve as a distraction."

In a statement shared with Fox News, Melinda Pierce, Sierra Club's legislative director, concluded the allegation of collusion is a "false conspiracy theory."

Vladimir Putin

Russian President Vladimir Putin has signed into law legislation that could punish journalists with up to 15 years in prison for reporting so-called "fake" news about his military invasion of Ukraine.        (Yuri Kochetkov/Pool)

"This false conspiracy theory, invented by the same deceitful front groups paid to do polluters' and big tobacco’s dirty work, has been repeatedly debunked over its nearly 10-year existence," Pierce said. "The Sierra Club has no connections to Russia or China, and proudly fights for clean energy and climate action because this is what our planet requires, our families deserve, and what the overwhelming majority of Americans across the country demand."

CLICK HERE TO GET THE FOX NEWS APP

The Republican Study Committee is the largest group of conservatives in the House. They've been hitting Biden hard for his domestic energy policies they say stifle domestic oil and gas production and led to the U.S. buying Russian oil to fund Putin's war against Ukraine. 

Biden announced this week the U.S. will stop importing Russian oil products and said "it's simply not true" that his administration is holding back domestic energy production.

Fox News' Kyle Morris contributed to this report.