Almost £60 million is sitting unused on prepaid Oyster cards, new data has revealed.

Figures from Transport for London (TfL) show £59.5 million is sitting on cards that have not been used for a year or more, up from £46.6 million in 2013, the Evening Standard reports.

Director of customer experience at TfL Shashi Verma disputed suggestions that TfL should make it easier for customers to claim the money back.

"Our customers tell us that this is a complete non-issue for them," he remarked, adding that many choose to keep hold of spare cards, and that some money is sitting on Oyster cards owned by infrequent visitors to the capital.

Leader of the Liberal Democrat London Assembly Group Caroline Pidgeon called for a publicity campaign on the issue.

"When did anyone recently hear from TfL that they were holding millions of pounds of public money which people have every right to claim back?" she asked.