WPS client implementation in R

I'm wondering what's the state of WPS (Web Processing Service) client
implementations in R? All I can find are the abstract of a 2008 UseR! talk:

https://www.r-project.org/conferences/useR-2008/abstracts/Henneboehl+Pebesma.pdf

and what looks like code designed to call a custom WPS server in the GSIF
package:

https://github.com/cran/GSIF/blob/master/R/WPSworldgrids.R

for a server that doesn't seem to work at the moment (wps.worldgrids.org).

Any advance on those?

Barry