The move consolidates Thomas Cook’s traditional media account with its £15 million digital media business, already handled by Carat Manchester.
Thomas Cook’s media account was among the first wave of sizeable brands won by Arena when it launched as BLM in 1990.
The agency, now owned by Havas, successfully fended off attempts to consolidate the business into Carat Manchester (then MediaVest Manchester) after a lengthy pitch process in November 2010.
The loss is a major blow to Arena, which is still attempting to stabilise itself after a series of senior departures following management earn-outs in 2011. The chief executive, Steve Booth, continues to lead the business.
Aegis Media was unable to confirm it had been awarded the business.
Separately, Thomas Cook has approached agencies ahead of a digital pitch as the travel brand seeks an overhaul of its digital presence.