Consultation has begun with around 100 staff across Marsh"s regional offices as it begins to restructure and implement its new business model.
It is understood the majority of its staff in the Exeter office have begun a 90-day consultation process, while about 20 staff out of 130 in its Birmingham office are in discussions with the broker.
Reports last week in the local Essex press said that 40 out of 700 staff would be shed at Marsh"s Witham office though many would be "redeployed" wherever possible across the wider business.
Marsh announced its new business model on 11 April, outlining that the broker would be simplifying its UK regional structure by creating "centres of excellence" for administrative processes, though it will remain a presence in all its 24 locations.
It is understood both Southampton and its Manchester offices will be affected by the changes. Though Southampton, which could lose around 40 staff, will be the base for Marsh"s SME business.
A Marsh spokesman would not confirm the figures but said of the consultation process: "We regret having to take these actions, but they are necessary in order to achieve the level of operating efficiencies our clients deserve.
"It is our intention to retain a number of employees in client liaison roles
who will act as direct points of contact for existing clients and new business in the area."