A British banknote manufacturer is working to develop passports that can be embedded directly into a holder's smartphone.

De La Rue, which produces banknotes and passports for dozens of countries around the world, said it was working towards creating a secure system of paperless passports.

The company's chief executive Martin Sutherland said in Tuesday's The Times that the project involved adapting its existing identity technology to a digital format that would be accepted at immigration control at borders.

Many airlines already offer digital boarding passes which passengers can download onto their smartphones before they arrive at the airport.

But Sutherland said their development work, which could create an era of paperless passports, was still in its infancy and would require governments to approve its use, The Times reported on Tuesday.

De La Rue is one of the world's largest printers of secure documents, producing banknotes for more than 150 countries worldwide including Britain, Fiji and Uganda.

The company also prints hardcopy passports for the U.K. and other countries, but has been under pressure to diversify its business after issuing several profit warnings since 2013.