Not true. With recycling, there is more than enough in just mill tailings on the surface right now to supply every watt of power needed for the next 600 years.
Going with the old-school semantics that reserves are known and avaialable, while resources encompass reserves as well as what is not yet discovered, or what is not yet avaialable with current technology. Sorry for the dated syntax. Does that mean I'm an old geezer yet?