Plans for North Wales Police to change their uniform to an all-black outfit have run into opposition.
The new design features black shirts and combat trousers
The traditional uniform of white shirt and tie is to be replaced with a black roll-neck top and worn with black combat trousers from the new year.
Police officials said the lightweight design was more practical for officers wearing body armour, but some local MPs claimed the look might be intimidating.
Conservative David Jones said it would give officers a "sinister" appearance.
The secretary of the North Wales Police Federation, Richard Eccles, said the current uniform had become outdated.
"What we have at the moment are officers wearing a dress shirt and a tie, which often tend to get jammed and clogged up under body armour," he said.
"Wearing a thick and heavy protective garment on top of a cotton shirt meant that as soon as you start walking round the officer would be soaked through with sweat.
"Combat trousers have already been in circulation for 12 months and it is now hoped to introduce a black garment for officers to wear under their body armour as well.
"There has been no adverse reaction from the public so far and the officers love the idea.
"A dress shirt and a tie is great in the office but does not really suit the action police officers often face nowadays."
But some local MPs said they were concerned about the connotations of an all-black uniform.
David Jones, Conservative MP for Clwyd West said he thought the new uniform might make officers look intimidating.
"I think it would give a sinister, unfriendly appearance to the police, which is exactly the opposite of what the police should be.
"I don't think that's the sort of uniform a British police force should be wearing.
"I think that the connotations of black shirts are obvious to anybody. They've got a kind of fascist, militaristic appearance.
"It may be appropriate for a police force in some tin pot central American dictatorship, but it certainly doesn't belong on the streets of places like Colwyn Bay and Ruthin."
A total of 20 officers from the force have been involved in trials of the new outfit over the last 12 months, and in September the new design was given the go-ahead.
A North Wales Police spokeswoman said: "We have been conducting trials of various uniforms over the last 12 months.
"We can confirm that in January all operational officers will be wearing black roll-neck tops."
Strathclyde Police decided to update its uniform in 2002 - the first major change in style since the 19th Century.
Switching to an open-necked shirt and black cargo trousers, the force explained the changes had been introduced "to meet the officers' needs and to contribute to the effectiveness of the police uniform".
The force added that the new-style uniform was "more suited to the demands of modern policing".