Shares in Trinity Mirror dropped 6.16% to 434p, a fall of 31p, after the company said it would wipe 12p off its cover price as part of a campaign to boost the paper's circulation, following changes to its masthead and treatment of news.
However, despite the fact that Trinity Mirror is backing the marketing push with an advertising campaign aimed at attracting younger readers to the paper, it will be hard pushed to make any gains on The Sun, which leads the Mirror by more than 1m readers.
The Mirror's price-cutting campaign was immediately met with the news that The Sun, owned by News International, part of News Corporation, has also dropped its cover price to match the 20p price of the Mirror.
Express Newspaper's Daily Star took even more drastic action, cutting its price from 30p to 10p.
The Daily Mirror lags more than 1.1m copies behind its rival. In March, it reported an ABC of 2,116,281, compared with The Sun's 3,379,716.
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