Markel is merging its wholesale segment with its global insurance division into a new entity to be known as Markel Assurance.

The combined unit will be led by Bryan Sanders, current president of the wholesale excess and lines segment, and is expected to be operational by 1 January 2018.

The transition will be assisted by Britt Glisson, who will retire at the end of 2018 following a 40-year career in the industry, most recently as president of Markel's global insurance division which includes complex, risk-managed accounts.

The company said that the combined division’s annual gross written premium is around $1.8bn and will originate from casualty, professional liability and property/marine lines of business, adding that leads for each line will report to Markel’s chief underwriting officer Robin Russo.

Markel Assurance will be made up of underwriting teams based in 10 US offices as well as Bermuda, Dublin and London.

Markel co-CEO Richard Whitt said that the move “aligns our structure more closely with both production partners and customers”.

"We are committed to innovation and to making it easier to do business with Markel—establishing this new division accomplishes both of those objectives,” he added.