Blank has opposed pressure from investors to sell Trinity Mirror's national newspaper division and focus on its profitable regional arm. The national division consists of the Daily Mirror and its Sunday sister, as well as The People and Scottish titles The Daily Record and The Sunday Mail.
Previously interested buyers have included Candover in 2003 with a £500m offer for the national titles, and new speculation about a sale should bring a queue of private equity houses and possibly David Montgomery, the former chief executive of the Mirror Group turned investor.
Mirror Group merged with regional publisher Trinity seven years ago and the process was overseen by Blank.
Trinity Mirror appears resigned to managing circulation decline at the Mirror, while fighting to maintain its market share.
The paper's six-month average circulation is down 3.38% year-on-year to 1.717m, while The Sun, which this week unleashed a major DVD giveaway, is down only 1.32% to 3.258m.
Blank is believed to have resigned in order to take up the chairmanship of Lloyds TSB, although this has not been officially confirmed.
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