Trenwick Group, the Bermuda-based insurance and reinsurance group, has announced changes at its UK operation.

Michael Watson will become chairman of its London subsidiaries, Chartwell Managing Agents and Trenwick International, from May 1. He was previously chief executive of Fairfax Financial Holdings' London and Bermuda operations.

Watson replaces Pierre Croizat, who is retiring.

David Marshall, the active underwriter of syndicate 839, is leaving the group. His successor is yet to be announced.

James Giordano, senior vice president and chairman of the underwriting committee of Trenwick America Reinsurance Corporation, will relocate to London to become underwriting director of Trenwick's UK operations.

James Billett Jr, chairman and chief executive of Trenwick said the changes were in response to its acquisition of Chartwell Re.

“We believe we are on target to meet the expense synergies and performance targets we set for London within the two-year time span we allotted when we acquired Chartwell Re in 1999,” he said.

Billett paid tribute to Croizat who joined Trenwick three years ago, and said he had placed the company's Lloyd's operations on a solid financial foundation.