A retailer in Limerick is under investigation by the Central Bank for using a "mock" €10 note in a promotional campaign.
Solo, a fashion store in Little Ellen Street, incorporated the banknote image on a flyer offering a €10 discount on purchases. The flyer has the same colour and size as a real "tenner", in apparent breach of European Central Bank guidelines on the reproduction of banknote images.
Some local businesses have reported people trying to pass the notes off as the real thing, albeit only as a prank. A spokesman for the Garda said it had no reports of complaints.
However, the Central Bank has expressed concern at the "mock" notes. A spokeswoman said it was "looking into the case".
She said: "The Central Bank is always concerned that the public would not be duped by things such as this, that they would not accept them at face value."
Defending the use of the flyer, the shop-owner, Ms Lorraine O'Connell, said: "I'm quite proud of it. A lot of flyers get thrown in the bin straight away. But money catches people's eyes."
She said she did not believe she was breaking any law, noting that the flyer was printed on glossy paper "so when you feel it you'll catch on".
Nor is it an exact replica of the €10 image, with the word "solo" replacing "euro" on the front-side and details of the promotion on the reverse.
Under ECB rules, which are enforceable across the EU, only one side of a banknote can be reproduced provided it is "more than 125 per cent or less than 75 per cent of both the length and width of the respective banknote".