The central bank promised to investigate alternative options when concerns were raised that the new £5 note, which went into circulation in September, contains tallow, a rendered form of beef or mutton fat.

But following discussions with supplier Innovia it has decided against halting the production process for the new batch of plastic tenners which are set to be introduced in September. It said it had spent £46m on printing the £5 note, and £24m so far on printing 275 million of the new £10 notes.

"Reprinting these notes on a new substrate would mean incurring these costs again. It would also require a further £50,000 for the secure destruction of the existing stock," says the Bank, adding that it "cannot guarantee" sufficient stocks of paper notes to replace the destroyed polymer notes.

However, the Bank says it is seeking further opinions on the use of animal-derived products and plant-based alternatives before making any decisions on the polymer used in future production runs of £5 and £10 notes

To this end, the Bank has delayed the signing of the relevant contracts for supply of materials for the £20 polymer note - which is set for issuance in 2020 - and will launch a full consultation on 30 March about the content of polymer substrate to be used in its future banknotes.

Dominika Piasecka, spokesperson for The Vegan Society, applauds the Bank for its transparency on the issue: "We have met with the Bank of England and believe they are committed to solving this problem and we will continue to work with them to find a good solution.

“We look forward to the consultation around the £20 note and hope that any future bank notes will be free from ingredients produced through harming animals. We hope that other companies will follow this positive example and review the use of animals in their products.”