The Home Secretary has announced that the starting salary for PCs in England and Wales is to be cut by £4,000 to £19,000.
The move comes following the Winsor review last year which proposed changes to police pay, conditions and allowances.
Mr Skates said: "It is particularly disappointing that the starting salary of a police officer will be cut in Wales, but will not be cut in Scotland. This seems very unfair and may only serve to undermine morale of officers here in Wales.
“We are at an all time low in terms of police numbers and putting a further restraint on recruitment will only exacerbate the problem. My own force in North Wales is already facing a 20% cut in funding over the next couple of years and now they will have this on top.
“Trying to penny-pinch when it comes to crime and anti-social behaviour will go down very badly in communities across Wales. I’m worried that this move will impact on the diversity of people coming into the force and put people off joining the police.
“The worry is that this will be the start of a bigger suite of changes to police officers terms and conditions. Plans are already circulating about allowing forces to make officers redundant.
“This not the time to be cutting back on police officers and the essential work that they do. These changes represent a false economy because figures released only last week show the number of young police officers in England and Wales had fallen by nearly 50% in two years.”