ACCOUNT CONTROL AGREEMENT

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                                                                   EXHIBIT 10.30
                                                                 [CITIBANK LOGO]

                            ACCOUNT CONTROL AGREEMENT

DATE: 19th SEPTEMBER 2002

Parties

CITIBANK N.A., AS "SECURED PARTY"

ALLIED WORLD ASSURANCE COMPANY LTD, AS "PLEDGOR"

MELLON BANK, N.A., AS "BANK"

ACCOUNT NUMBER

Background

Pledgor has granted Secured Party a security interest in the financial assets in
the securities account identified above (the ACCOUNT), maintained by Bank for
Pledgor, (including any security entitlement) and in the Account. The parties
are entering into this agreement to provide for the control of the Account as a
means to perfect the security interest of Secured Party. Bank has no
responsibility to Secured Party in respect to the validity or perfection of such
security interest otherwise than to act in accordance with the terms and
conditions of this Agreement.

Agreement

1. The Account

Bank represents and warrants to Secured Party that Bank maintains the Account.
Bank represents and warrants that except for the claim and interest of Pledgor
and Secured Party, or as provided in Section 4 of this Agreement, Bank does not
know of any claim to or interest in the Account or any financial assets credited
thereto. Bank, Pledgor and Secured Party agree that the Account is a SECURITIES
ACCOUNT as that term is defined in Section 8-501(a) of the Uniform Commercial
Code as in effect from time to time in the State of New York (the "NYUCC").
Bank, Pledgor and Secured Party agree that each item of property (whether
investment property, financial asset, security, instrument or cash) credited to
the Account shall be treated as a financial asset within the meaning of Section
8-102(a)(9) of the NYUCC.

2. Control by Secured Party

Bank will comply with all notifications it receives directing it to transfer or
redeem any financial assets credited to the Account (each an ENTITLEMENT ORDER
as defined in Section 8-102(a)(8) of the NYUCC) originated by Secured Party and
shall otherwise treat Secured Party as entitled to exercise the rights in
respect of any financial asset credited to the Account without further consent
by Pledgor.

3. Pledgor's Rights in Account

Subject to this Section 3, until Bank receives an entitlement order from the
Secured Party, Bank may accept and comply with any entitlement order from
Pledgor with regard to the Account or any financial asset as follows:

-           Until Bank receives an entitlement order from Secured Party, Bank
            shall distribute to Pledgor all cash distributions received in
            regard to financial assets in the Account. Cash distributions do not
            include any principal received upon redemption or maturity of a
            financial asset, and any such cash will be held for the benefit of
            Secured Party.

-           Prior to sending an entitlement order to Bank, Pledgor shall
            determine that the financial assets remaining in the Account will be
            equal to or exceed the aggregate value determined by Secured Party
            from time to time (the "Required Account Value"). For purposes of
            determining the value of any financial asset Pledgor shall (i)
            determine that the financial asset is eligible as collateral as
            specified in Exhibit A


                                      -1-


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            hereto and (ii) use the mark-to-market value provided by pricing
            services used by Bank in connection with the valuation of financial
            assets under similar account control arrangements or for Bank's
            trust accounts, in each instance after applying the discount
            specified in Exhibit A hereto; provided that in determining if the
            remaining financial assets are sufficient Pledgor shall use the