The group is in discussions with Brunswick, The Maitland Consultancy and the incumbent over the business.
It is thought that Financial Dynamics – which works for publishing house Bloomsbury – and Tulchan Communications, which represents Daily Mail and General Trust, are conflicted out of the pitch.
The winning agency will report to director of corporate comms Nick Fullagar.
Trinity Mirror Group, which declined to comment on what had triggered the review, was formed in 1999 after the merger of publishers Trinity and Mirror Group. Finsbury worked with the latter for a couple of years before the merger.
The group, whose HQ is at Canary Wharf, has struggled through the recent dip in off-the-shelf newspaper sales.
In May the company revealed group ad revenues had dropped by around 12 per cent year-on-year – and by 16 per cent in its UK national division, which includes flagship title the Daily Mirror. The Sunday Mirror and People revealed 4.9 per cent and 10.9 per cent sales falls respectively in April’s ABC figures.
Earlier this month, it was reported that the group was planning to sell off its trade and consumer magazines and exhibitions division, hoping to generate £45m-£50m in revenue.
Trinity Mirror has declined to comment on the speculation.