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EXHIBIT 99.7
[LETTERHEAD OF LAZARD FRERES & CO. LLC]
August 23, 2000
LaSalle Re Holdings Limited
Continental Building
25 Church Street
Hamilton HM 12
Bermuda
We hereby consent to the inclusion of our opinion letter dated December 19,
1999 as Appendix H to, and to the reference thereto under the caption
"SUMMARY -- Opinions of Financial Advisors -- Opinions of LaSalle's Financial
Advisors" and "THE TRANSACTIONS -- Opinions of LaSalle's Financial Advisors" in,
the Joint Proxy Statement/Prospectus of LaSalle Re Holdings Limited ("LaSalle")
and Trenwick Group Inc. ("Trenwick") relating to the proposed business
combination involving LaSalle and Trenwick, which Joint Proxy
Statement/Prospectus is part of the Registration Statement on Form S-4 of
Trenwick. In giving such consent, we do not thereby admit that we come within
the category of persons whose consent is required under Section 7 of the
Securities Act of 1933 or the rules and regulations of the Securities and
Exchange Commission thereunder.
Very truly yours,
LAZARD FRERES & CO. LLC
By: /s/ STEVEN J. NIEMCZYK
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Steven J. Niemczyk
Managing Director
