Details of the '3-DM' technique and the printer which the mail company has teamed up with were not disclosed but, according to the company, the effect can be viewed from any angle and gives the impression of visual elements within the design floating in three-dimensional space.

Customers wishing to use the service send in their design to TNT who will work them then to produce a sample that is ready to go within three weeks. The mailing can be enclosed in an envelope or sent as a postcard in either A6 or A5 format.

The premium in using the effect is in the region of 40p, the company said, based on an order of 8,000 pieces – although this price decreases with larger runs.

TNT Post UK chief executive Nick Wells said: "Direct mail is an excellent channel for achieving one-to-one communication with customers and more emotional intensity than any other medium... In a busy market, businesses are always looking for new ideas to gain cut-through.

"Our 3-DM product was specifically designed to give our customers more choice in DM design and a unique creativity that catches the eye and gets people talking."