In addition, the software, which is designed to enable advertisers to deliver display advertising directly to a publisher, has recently been adopted by the Guardian and the Observer, Vio has said.

The new software enables publishers to mandate a soft proof or to offer it as an option by publication or even by advertising type, the company said.

Gavin Page, European sales director of Vio Worldwide, said: "This latest innovation in Adsend marks the world's first 100% browser-based integrated calibration and proofing solution."

To develop the software, Vio has extended its long-term OEM partnership with Integrated Color Solutions (ICS), which Page said came from ICS's position as the "provider of the most complete suite of colour accurate virtual proofing products on the market".

In June, Mirror Group Newspapers became the first UK newspaper publisher to migrate to using the low-cost ad delivery software Adsend.