I don't know if it's connected to the 'climate change agenda', but Yellen does want a global corporate tax:
"Corporations around the world should pay at least a 15% tax on their earnings, the Treasury Department said Thursday as part of its push for a global minimum for businesses. The final rate could go even higher than that, according to a Treasury release that said the 15% minimum is a "floor and that discussions should continue to be ambitious and push that rate higher."
Treasury Secretary Janet Yellen has been touting the benefits of a global corporate minimum tax rate that she said would discourage companies from relocating domiciles to other countries to cut their tax burdens even though most of their operations are in the U.S."
https://www.cnbc.com/2021/05/20/us-proposes-global-minimum-corporate-tax-rate-of-15percent-with-an-eye-on-something-even-higher.html