The publisher distributed copies of the sampler to London commuters last week and on Tuesday this week (18 May), and will hand out a final edition next week.

Distributors targeted commuters at key stations across the capital, including Waterloo, Marylebone and Charing Cross.

The Berliner-sized 24-page sample paper is essentially a condensed issue of its parent title, and includes news, features and columns from the main paper.

This is not the first time that GNM has produced sample runs, but it is the first time that it has dubbed a sample version "the mini Guardian".

A spokesman for the paper told PrintWeek that, while sampling campaigns such as this were nothing new for the group, this current project was more sophisticated in its execution. Previous samplers were put together using existing articles, whereas this one used new content.

The Guardian said the campaign had been devised to build on its election coverage – both off- and online – as well as the heightened post-election news agenda.

Currently, the Guardian is printed at the GN&M-owned Guardian Print Centre, which comprises two print sites, in London and Manchester. The group's London site produced the "mini Guardian". The spokesman would not divulge the exact print run, but said it was in the "tens of thousands" for each day's edition.

As well as printing the Guardian and Observer, the centre also prints papers for third parties.

The Guardian said it had received good feedback from the campaign to date, adding that it would probably repeat the move, although it has no "immediate plans" to do so.

Last September, the Guardian Print Centre and Unite reached came to an agreement over redundancies, after a ballot over industrial action was proposed for the printer's London site.