New Delhi, Sep 21 (IANS): The exterior of some Delhi Metro trains will be available for advertising as the corporation will be permitting wraps to augment non-operational revenues, an official statement said Sunday.

"To augment the non-operational revenues, Delhi Metro has awarded exclusive rights for displaying advertising materials, including pictures, printed material, electronic media, posters, holographic images and visual displays on the external part of its trains," a Delhi Metro statement said.

Currently, Delhi Metro operates a fleet of over 200 train sets -- with over 60 eight-coach trains and over 80 six-coach trains.

"The train wraps shall be permitted on 10 percent of the total train sets available on the operational lines of the Delhi Metro network," it said.

The advertising rights, given to two agencies, shall be valid for 10 years.

So far, Delhi Metro has been allowing advertisements inside Metro trains and the station premises.