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                                                                    Exhibit 4.13



                             CERTIFICATE OF TRUST

                                      OF

                      TRENWICK AMERICA CAPITAL TRUST II

        THIS Certificate of Trust of Trenwick America Capital Trust II (the
"Trust"), dated as of June 15, 2001, is being duly executed and filed by the
undersigned, as trustees, to form a business trust under the Delaware Business
Trust Act (12 DEL. C. Sections 3801, et seq.).

        1.     Name.  The name of the business trust formed hereby is Trenwick
America Capital Trust II.

        2.     Delaware Trustee.  The name and business address of the trustee
of the Trust with a principal place of business in the State of Delaware is Bank
One Delaware, Inc., Three Christiana Center; 201 N. Walnut Street; Wilmington,
Delaware 19801.

        3.     Effective Date.  This Certificate of Trust shall be effective
upon filing with the Secretary of the State of the State of Delaware.





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        IN WITNESS WHEREOF, the undersigned, being the trustees of the Trust,
have executed this Certificate of Trust as of the date first-above written.

                               BANK ONE TRUST COMPANY, N.A., as trustee
                                  of the Trust

                               By:         /s/ Sandra L. Caruba
                                   ---------------------------------------
                                   Name:     Sandra L. Caruba
                                           -------------------------------
                                   Title:    Vice President
                                           -------------------------------


                               BANK ONE DELAWARE, INC., as trustee of the
                               Trust

                               By:         /s/ Sandra L. Caruba
                                   ---------------------------------------
                                   Name:     Sandra L. Caruba
                                           -------------------------------
                                   Title:    Vice President
                                           -------------------------------

                               JOHN V. DEL COL, as Administrative Trustee


                                           /s/ John V. Del Col
                               ------------------------------------------
                                           John V. Del Col



                               YVONNE M. POSTER, as Administrative Trustee


                                           /s/ Yvonne M. Poster
                               ------------------------------------------
                                            Yvonne M. Poster



                               DAVID M. FINKELSTEIN, as Administrative
                                 Trustee


                                           /s/ David M. Finkelstein
                               ------------------------------------------
                                            David M. Finkelstein