The money, produced by an anti-Brexit group, mock British Prime Minister Boris Johnson and Leader of the House of Commons Jacob Rees-Mogg, The Guardian reported.
A "Bank of Brexit lies" banknote with Johnson, which uses a £10 note design has a £350 million nominal "value", and says "I promise not to pay the NHS the sum of £350m pounds". The "£50 guinea" note with Rees-Mogg says "I promise to pay myself more than you".
According to the newspaper, the unusual notes were designed and then propagated by the Bath for Europe group, which campaigns to stop Britain leaving the EU.
Tom Hockenhull, curator of modern money at the British Museum, stated that the parody notes "captured history" and said any pro-Brexit notes would be also welcomed as well.