The council said anyone taking the advice of the signs could be prosecuted
People should ignore signs telling them that it is legal to urinate in certain public places in Nottingham, the city council said.
The signs, which were put up by pranksters in and around Nottingham, are designed to look official.
They feature a toilet sign and include the words: "Public Urination Permitted After 7.30pm".
Nottingham City Council is now urging the public to ignore the notices as it sets about removing them.
The prank also featured a laminated note, headed with the logo of Nottingham City Council, which said the scheme was aimed at reducing the mess faced by residents outside their homes.
A spokeswoman for the authority said: "It is an offence to urinate in public and these signs have been put up illegally, for whatever reason.
"We would urge people to ignore them, otherwise they could find themselves inadvertently facing a prosecution.
"We are taking the signs down as quickly as possible and if anyone spots one of the illegal signs we ask them to please contact the city council so they can be removed."
The notice reads: "In an attempt to reduce late night public nuisance, during the holiday period, Nottingham City Council has designated several public urination areas across the city.
"This urination area will be cleaned daily between the hours of 5am and 6am."