The Bank of England has admitted that new plastic bank notes due to be issued later this year may stick together.
In an official factsheet on the new notes, the Bank said the new notes will be tougher and more secure – but admitted they may prove difficult to prise apart.
The Bank said: “Brand new polymer notes can sometimes stick together, but this effect is short-lived once in use.”
A new £5 will be issued in September 2016, along with a new £10 note in 2017, and a new £20 note by 2020.
The full design of the new £5 note, which is set to feature Sir Winston Churchill, will be unveiled on Thursday.
The new notes will be around 15% smaller than the current paper notes but will retain the traditional look of the existing notes, with a portrait of the Queen on the front and historic characters on the back. The new banknotes will include symbols representing all four home nations, with imagery taken from the Royal Coat of Arms and the Royal Badge of Wales.
More than 30 countries currently issue polymer notes, including Australia, who introduced them in 1988, New Zealand, Mexico, Singapore, Canada and Fiji.