Bitcoin may not be as bad for the environment as people think, U.S. Democratic presidential candidate Robert F. Kennedy Jr. suggested in a Twitter post on Sunday, though he did not say that this was his official stance.

“At the very least, environmental argument should not be used as smokescreen to curtail freedom to transact,” wrote Kennedy Jr, who is a long-time environment advocate, reiterating a point he made last week at a Twitter space hosed by bitcoin investor Scott Melker.

Some environmentalists and policy makers have expressed concerns around bitcoin’s environmental impact due to the massive amounts of energy that are used to mine bitcoin. However, Kennedy has been courting bitcoin supporters lately, as well as advocating on their behalf.

Last month, the presidential candidate said that if elected, he planned to exempt bitcoin from capital gains tax when it is converted to U.S. dollars and that he would back the U.S. dollar with finite assets like gold, silver and bitcoin. His campaign debut was in May at the Bitcoin 2023 conference hosted in Miami.

Kennedy is a bitcoin investor himself. “Right after the bitcoin conference, I decided to put my money where my mouth is and bought two bitcoin for each of my seven children,” Kennedy said during last week’s Twitter space.

The presidential candidate is also known for trying to combine good business policies with ambitions to improve the environment, and once said at a conference in 2016 that “good environmental policy is good for economic prosperity.”

Americans will go to the polls to elect a president on Nov. 4 next year and so far incumbent president Joe Biden has been leading Kennedy by upwards of 50 points in recent polling.

Read more: RFK Jr. Vows to Back Dollar With Bitcoin, Exempt BTC From Taxes