It has no constitutional basis. They are referring to it with the term used in european Parliamentarian governments. It is not constitutional in the US. They might as well hold a "guy we won't invite to our Ice Cream party vote". At least that would represent the seriousness of their vote.
Imo it's probably so they can get points with their eurotrash friends when they go on summer vacation. GWB really irks the eurotrash elites which makes the US trash-elites uncomfortable when they vacation alongside their eurotrash bretheren. Heh, I've witnessed it firsthand.