Managers at Leeds Bradford Airport broke the rules by failing to get planning permission before putting up roadside signs which warn approaching drivers about a £2 airport toll which has angered many passengers.
The notices, placed in White House Lane, break the guidelines relating to style, content and the size of the letters.
Airport managers have declined to comment on the blunder, described by a councillor as a “PR disaster” coming on the back of the controversial drop-off charges.
The airport has now been told to take down the signs.
A Leeds Council spokesman said: “The new signs on White House Lane alerting passengers to the new pick-up and drop-off arrangements at the airport do not meet national road sign guidelines. We have spoken with the airport and will ensure they resolve the matter as quickly as possible.”
Local councillor Colin Campbell, who represents Otley and Yeadon, described it as a “PR disaster”.
“I think it’s unfortunate that the airport has chosen to do this.
“I am sure they know, with their previous experience with the planning process, that they should have applied for planning permission.
“If you are putting up signs on the highway you do need to get the okay from the planning department and from highways.”
The signs were put up last month when the £2 charge was introduced for any motorist wanting drop off or pick up passengers outside the terminal building.
There was previously no charge for under 10 minutes, and the new fee rises to £5 after half an hour.
Drivers can use the long-stay car park, which is half a mile from the terminal and is free for up to an hour.
Coun Campbell said that it appeared the airport company was trying to maximise income at the expense of being “as people-friendly as they should be”.
Although passengers may be angered, Coun Campbell said he did not think the £2 charge would encourage people to use different airports such as Manchester.
But he added that the imposition of the new charges said something about the attitude of the airport towards passengers.
“Airports make as much money from activities on the ground as they do from aeroplanes. This is an attempt by the airport to maximise its income.”
A former airport worker, who asked not to be named, said the airport “never applied for planning permission, they just banged them up. As soon as someone from highways came down, they told them they didn’t comply with the law.”
Councillor Andrew Carter, leader of the Conservative group on Leeds City Council, has previously branded the drop-off charge a “rip-off”.
And angry taxi drivers have launched a petition calling for it to be scrapped.
Frequent flyer Professor Paul Kind, of York University, is among the passengers annoyed at the new charges.
He said the road signs were a “victory for incompetence.”
“It indicates to me that this whole thing has been half-cocked, badly planned and badly executed,” he added.
A spokeswoman for the airport declined to comment.