SCOTTISH polymer banknotes contain "minute traces" of animal fat, the company who makes them has admitted.

Banknote printer De La Rue said that detailed analysis had revealed "animal derivative" equivalent to a maximum of 0.003 per cent in each note.

The admission came after three main Scottish banks, Clydesdale Bank, Bank of Scotland and Royal Bank of Scotland, said that the new £5 notes were vegan-friendly.

The row over the traces of animal product has rumbled on this week, with more than 100,000 people signing a petition objecting to the use of tallow derived from animals in the notes.

A De La Rue spokesman said: "Our initial analysis of our supply chain suggested that our polymer substrate did not contain any traces of tallow, and we advised specific customers on this basis.

"However, recognising the concern expressed by the public in recent days, we have undertaken a detailed and thorough review of our polymer supply chain. This review has identified the potential for minute traces of animal derivative, equivalent to a maximum of 0.003% per banknote.

"We are now working with our suppliers to identify ways of addressing this."

The petition, on the Change.org website, calls on the Bank of England to "cease to use animal products in the production of currency that we have to use".

It states that tallow is "unacceptable to millions of vegans, vegetarians, Hindus, Sikhs, Jains and others in the UK".

A number of Sikh and Hindus have also urged the notes be banned from temples, where meat products are forbidden.

Polymer notes are more durable than the paper ones. They are expected to last an an average of five years, compared to two years previously.