Gardaí who wish to have a beard should "smarten up" and decide to grow a proper one or none at all - that's what a Garda supervisor has told his junior officers.

The inspector - who works in a traffic unit - said that some gardaí "cannot seem to make up their minds" if they want a beard or not because they alternate on a weekly basis between "being clean shaven to having various stages of facial hair".

This was "unacceptable" he wrote in an internal circular to Garda sergeants.

The inspector compared some of the attempts by gardaí to grow beards as resembling "a badly watered lawn in a heatwave".

The decision to grow a beard should not be interpreted by gardaí "as an excuse to take a break from shaving" he advised.

"In short, members should decide whether they want a beard or not (or whether their partners will allow them to have one or not) and commit to one look or the other," he said.

He also pointed out that two weeks is the advised maximum time to sufficiently grow a beard and those that cannot do so should "concede and graciously admit defeat".

The Garda Commissioner, Drew Harris, updated the Garda’s Dress and Uniform Code last July which made several changes including allowing gardaí to grow a beard.