The Daily Mirror has spoofed the Sun's topless Page 3 model feature in the opening salvo of a campaign to position itself as "smarter" than tabloid rivals.

On Monday the Trinity Mirror daily replaced its typical Page 3 layout with a full page ad that mimics the Sun's tradition of using a shot of a scantily clad model.

The ad features a model in a bath with her arms crossed and elbows poking out giving the appearance, at first glance, of a pair of bare breasts.

However, the image proved too risqué for poster sites on the London Underground, with Transport for London refusing to allow it to be run.

Trinity Mirror's campaign features the strapline "We're not like other tabloids" and the hashtag #Madeyouthink.

"This ad certainly makes you stop and think and it was clearly too edgy for TfL," said a Trinity Mirror source.

The issue of the use of Page 3 girls is a contentious one, with campaigners continuing to vociferously lobby for the Sun to drop the long-running feature.

Last week Mike Darcey, the chief executive of Sun publisher News UK, defended the practice, claiming that most male and female Sun readers "strongly support" its Page 3 strategy.

Trinity Mirror's brand campaign, the first for the Daily Mirror and Sunday Mirror in 10 years, comes after the two titles launched their first design revamp since 2007 over the weekend.

"There's one thing that really makes the Mirror stand out from the tabloid crowd – we have a brain and so do our readers," said a source. "And that's the message we're driving home here."

A TV campaign, also developed by ad agency Quiet Storm, will launch at the end of the week.

The Daily Mirror and the Sunday Mirror's design revamp features new fonts and a "less frenzied" colour palette.

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