U.S. environmental activists who are working to halt the production and use of fossil fuels could be required to register as foreign agents if Congress gets serious about enforcing an existing law.

There was some potential movement in that direction last October when Senate Judiciary Committee Chairman Chuck Grassley, R-Iowa, introduced legislation that would put some teeth into the Foreign Agents Registration Act. The law, which was first passed in 1938, calls for individuals and organizations to provide full disclosure when they are working to advance the public policy interests of a foreign government.

As the Washington Examiner has reported, Grassley’s proposed legislation would close off an exemption that has allowed lobbyists for foreign interests to avoid registration while providing the U.S. attorney general with additional authority to conduct investigations.

While the media remains largely focused on ongoing investigations into allegations of Russian interference in the 2016 campaign, the connection between Vladimir Putin’s government and U.S. environmental groups deserves more scrutiny.

Klein Ltd., a Bermuda-based shell corporation run by executives with strong ties to longtime Putin friend Leonid Reiman and Russian energy investment groups including Firebird New Russia Fund and Vimpelcom Ltd., reportedly funneled $23 million to the Sea Change Foundation, according to a detailed 2014 U.S. Senate Environment and Public Works Committee report.

Klein’s legal counsel dismisses such charges as “completely false and irresponsible.” But in a letter addressed to U.S. Treasury Secretary Steven Mnuchin, members of Congress document evidence pointing to a paperless money trail that flows from Russia into U.S. environmental groups through the Sea Change Foundation. The implication is that the Russians have been pouring tens of millions of dollars into willing environmental advocacy groups in an effort to spread propaganda directed against fracking in the U.S. and the technology that makes it possible, according to evidence presented in the letter.

Rep. Lamar Smith, R-Texas, chairman of the House Committee on Science, Space, and Technology, and his colleagues have called on the U.S. Treasury Department to conduct an investigation into the allegations of Russian collusion with U.S. environmental groups. In response to a media inquiry I sent last year asking about the allegations, a U.S. Treasury spokesman said in an email message, “We respond as appropriate to Congressional inquiries, but wouldn’t comment publicly on an investigation.”

The motivation for Russian interference here is clear. As the congressional letter notes, American ingenuity in the oil and gas industry have significant geopolitical ramifications. Thanks to innovative extraction technologies such as hydraulic fracturing and horizontal drilling, the U.S. now has access to vast reserves of oil and gas previously held to be unrecoverable. The unexpected energy resource bonanza has dramatically shifted the dynamics of the economic and geopolitical landscape in America’s favor.

The U.S. is the top producer of natural gas in the world. In 2016, U.S. natural gas imports set a record low even though consumption has increased. In 3 of the first 5 months of 2017, U.S. natural gas exports were greater than imports — the growing trend points to the U.S. becoming a net exporter. This new commitment to natural gas means less expensive energy bills for consumers as well as economic, environmental, and national security benefits for the country as a whole. The U.S. Chamber of Commerce estimates that the fracking boom has created 2.7 million jobs, with an estimated additional 3.5 million projected by 2035.

From a foreign policy perspective, the U.S. can now export liquefied natural gas to parts of Europe that have been dependent on Putin’s government for their gas. This weakens Putin and puts the U.S. in a stronger position to exert influence. Up until now, periodic disputes with Russia have resulted in economic bullying tactics from Moscow that include wintertime threats to close pipelines supplying oil and natural gas. Those days may be over now that American natural gas development is poised to impact Russia and its Gazprom oil company.

However, an international campaign known as “Keep It in the Ground” has been pushing an anti-fossil fuel agenda that advances Russia’s geopolitical interests at the expense of the U.S. and America’s allies. The campaign claims support from more than 400 organizations across the globe, with a sizable percentage operating inside the U.S. The campaign is opposed not just to the extraction of fossil fuels, but to any fossil fuel-related project including pipelines, rail transportation, refineries, and energy exploration.

These groups include Greenpeace, the Sierra Club, 350.org, the Center for Biological Diversity, WildEarth Guardians, the Rainforest Action Network, Earthworks, and the Chesapeake Climate Action Network, to name just a few. Some of the larger environmental advocacy groups in the U.S., such as the Natural Resources Defense Council and the League of Conservation Voters, don’t appear on the list of 400, yet do support the same anti-fossil policy aims and draw from the same pool of financial supporters.

The common denominator here between many of these groups is the San Francisco-based Sea Change Foundation, which has been identified as the incubator for Russian funding of environmental groups. Another key player is the Energy Foundation, which is also based in San Francisco and appears to be an offshoot of the Sea Change Foundation.

If Grassley succeeds in bolstering the Foreign Agents Registration Act, a good starting point for an investigation would be with the “Keep It in the Ground” campaign members and with other environmental groups that support the campaign’s agenda.

While these groups are free to advocate for their preferred policies, they should not be permitted to posture as grassroots activists if they are in fact doing the bidding of foreign interests, to the detriment of average Americans who benefit from affordable and reliable sources of energy.

Kevin Mooney (@KevinMooneyDC) is a contributor to the Washington Examiner's Beltway Confidential blog. He is an investigative reporter in Washington, D.C. who writes for several national publications.

If you would like to write an op-ed for the Washington Examiner, please read our guidelines on submissions here.