The Bank of England has decided to carry on using chemicals derived from animal products to make its new plastic banknotes despite an outcry.
An extensive consultation saw the vast majority of those who responded say they were against the use of the additives.
But the Bank said the alternative of using palm oil raised environmental concerns and would cost the Treasury an extra £16.5m over the next ten years.
The Government told the Bank it did not believe a switch would be achieve value for money for taxpayers.
Campaigners launched a petition last autumn after it emerged that the new plastic £5 note contained traces of an animal product derivative.
The Bank launched a review following the outcry and earlier this year decided not to scrap the notes, though it said it would hold a public consultation into the production of future notes.
It has now said that after “careful and serious consideration… there will be no change to the composition of polymer used for future banknotes”.
“The new polymer £20 note and future print runs of £5 and £10 notes will continue to be made from polymer manufactured using trace amounts of chemicals, typically less than 0.05%, ultimately derived from animal products,” the Bank said.
Its consultation involved outreach meetings with affected groups, technical trials, commercial discussions and commissioning independent environmental research.
There were also responses by 3,544 people. Of these, 88% were against using animal products and only 48% against using those made from palm oil.
But the Bank said it had to balance this “against its other public duties and priorities” and other evidence it had gathered.
“The use of palm oil raises questions about environmental sustainability and the Bank’s suppliers have been unable to commit to sourcing the highest level of sustainable palm oil at this time,” it added.
“The Bank fully recognises the concerns raised by members of the public, both prior to and during the consultation, and has not taken this decision lightly.”