Bailey said it was too early to speculate about whether the company will decide to split its national and regional publishing assets, but a sale of its troubled Mirror titles is now a definite possibility. "We do not rule anything in, we do not rule anything out, " she said. "It is time for a good hard look at what we do."

There was no single catalyst for the review, Bailey said, and that there have been no approaches from other parties to buy either of its divisions. "This is about us being on the front foot, " she added, and the review should be finished by the end of the year.

Trinity Mirror has long refused to entertain the prospect of selling its Mirror titles, which also include The People, despite investor pressure.

But the departure of former chairman, Victor Blank, who fervently refused to unwind the 1999 merger of Trinity's regional titles and the Mirror papers, is believed to be a factor in clearing the path for a potential break-up.

Like many of its peers, Trinity Mirror has struggled to cope with a marked downturn in advertising spend as circulation has fallen and more classified advertising has moved to the internet.

Slowing economic growth, sluggish consumer spending and higher unemployment rates in Britain have also hindered its progress, Bailey said.

Excluding acquisitions, Trinity Mirror's revenue fell 7% during the first half of the year, while pre-tax profit dropped 13% to £98.1m.

The company also booked an impairment charge of £250m related to the carrying value of its regional titles, which recorded a near 10% decline in advertising revenues.

"Clearly a write-down of this magnitude is negative, " Numis Securities stated afterwards, "particularly as it follows on from Daily Mail General Trust's decision to sell its regional portfolio, which was subsequently pulled when the offers failed to meet expectations."

Bailey's strategy has been to rapidly reduce the cost base at Trinity Mirror, with £16.7m sliced out in the first half alone. A major part of the strategic review will involve looking at ways to find more savings, though Bailey said that would focus more on improving efficiency than significant job cuts.

While cutting costs, Trinity Mirror has also been investing heavily in online advertising.

It has launched or purchased 227 websites in the past eight months, predominantly in the regional classified advertising sector for the recruitment, property and motoring markets.

The review at Trinity Mirror would "crucially reignite speculative M&A interest, " Bridgewell Securities said in a note. "Certainly, a Trinity Mirror excluding national newspapers is more attractive to the venture capital community than it is at present."