The system uses existing elements of the design to trigger a smartphone to visit an online property or additional digital content when scanned using the phone's camera.

Users need to have downloaded a free app, available today on both iPhone and Android platforms.

The platform was developed by Royal Mail's Door to Door unit and Digital Space. Royal Mail's chief customer officer Dave Smith said: "This landmark partnership means that Royal Mail is the first postal company in the world to offer digital watermarking technology to its customers.

"By using this technology, businesses can ensure their mail campaigns are as effective as possible by linking directly to their websites, videos and even social network pages."

Potential applications could be linking through to a video of a holiday destination or a how to guide on preparing a recipe.