A Wall Street bank is again being attacked for its ESG investment policies, but this time from an environmental advocacy group.

The group, which calls itself Vanguard S.O.S., said in a press release that it plans to run an ad starting today that criticizes Vanguard's lack of adherence to ESG principles. The ad will run on CNBC and on cable systems in Chester County, Pa., where the fund giant is headquartered and where many of its top executives and employees live, the group said.

The 30-second ad accuses Vanguard of “taking its marching orders” on climate change from climate-change-deniers, including Rep. Marjorie Taylor-Green, a Republican from Georgie, and Senator Ted Cruz, a Republican from Texas. The ad comes at a time when ESG investing is under heavy attack from the Republican Party and other conservative groups.

"The purpose of the campaign is to shine a spotlight on Vanguard’s refusal to mitigate climate risk. Vanguard is the world’s largest investor in fossil fuels, with nearly $300 billion in exposure, including nearly $100 billion in coal alone," the group said in the press release.

The ad will simultaneously run on streaming television platforms, including Hulu and YouTube, according to Vanguard S.O.S., which is an international organization made up of civil society organizations, social movements, and financial experts. 

When asked for a response, Vanguard spokesman Netanel Spero did not comment on the ad specifically but said, “Our approach to climate risk is about safeguarding investor returns.

“Climate change has far-reaching economic consequences for companies and financial markets—and therefore, for our investors. As a result, climate risk is a material financial risk for companies and their shareholders. We take this risk to our investors seriously. On behalf of the internally managed equity funds, Vanguard’s Investment Stewardship team engages with those companies to better understand how boards disclose, address, and oversee material risks—including climate risk."

The ad is part of an ongoing campaign by Vanguard S.O.S., which warns Vanguard’s customers and employees that climate change is a risk to their retirement plans and accuses the firm of being one of the slowest financial firms to consider the risk when investing clients’ money.