EXHIBIT 99(d)




White Mountains to Acquire Sirius Insurance Group

HAMILTON, Bermuda, Dec. 9 /PRNewswire-FirstCall/ -- White Mountains Insurance
Group, Ltd. (NYSE: WTM) announced today that it has entered into a definitive
agreement with ABB Ltd. to acquire the Sirius Insurance Group, an insurance
and reinsurance organization based in Sweden, at a purchase price of SEK3.22
billion (approximately US$425 million). The purchase price is subject to a
kronor- for-kronor adjustment to the extent that the total tangible
shareholders' equity value of the acquired companies as of December 31, 2003
is greater or less than SEK3.566 billion (approximately US$470 million).

The principal Sirius International Group companies are Sirius International
Insurance Corporation, Sirius America Insurance Company and Scandinavian
Reinsurance Company Ltd. Sirius International, a Stockholm-based reinsurance
company, is the largest reinsurance company in Scandinavia and has offices in
Stockholm, London, Hamburg, Zurich, Belgium, and Singapore. Sirius
International wrote approximately $400 million in net premiums in 2002. The
company focuses mainly on property and other short-tailed lines and no longer
writes financial insurance products. Sirius America, a US insurer focused on
primary insurance programs since 2000, wrote $96 million of net premiums in
2002. Scandinavian Re is a Bermuda-based finite reinsurer that is in runoff.

The Sirius International Group has a large safety reserve that is considered
Swedish regulatory capital (approximately $900 million at September 30, 2003)
but is reduced by a deferred tax liability under US GAAP. Reserves on the
Scandinavian Re finite book are carried at ultimate values for US GAAP prior
to purchase accounting.

"This acquisition leverages all the strengths of the White Mountains
organization. We delivered a clean exit from the business to ABB, we were able
to do so quickly, we are adding a nice business to our family of
property/casualty insurance and reinsurance companies and the transaction adds
significant value for our shareholders," said CEO Ray Barrette. "Sirius'
management has focused on property and other short-tailed lines of business,
allowing them to avoid most of the legacy issues that other international
reinsurance companies are facing today. This is an outstanding team that
shares White Mountains' core belief that underwriting comes first," he added.

White Mountains expects the transaction to close in the second quarter of
2004. The transaction is subject to regulatory approvals and other customary
closing conditions.

ADDITIONAL INFORMATION

White Mountains is a Bermuda-domiciled financial services holding company
traded on the New York Stock Exchange and the Bermuda Stock Exchange under the
symbol WTM. Additional financial information and other items of interest are
available at the Company's web site located at www.whitemountains.com. Safe
Harbor Statement under the Private Securities Litigation Reform Act of 1995
This press release may contain "forward-looking statements" within the meaning
of Section 27A of the Securities Act of 1933 and Section 21E of the Securities
Exchange Act of 1934. All statements, other than statements of historical
facts, included or referenced in this release which address activities, events
or developments which we expect or anticipate will or may occur in the future
are forward-looking statements. The words "believe," "intend," "expect,"
"anticipate," "project," "estimate," "predict" and similar expressions are
also intended to identify forward-looking statements. These forward-looking
statements include, among others, statements with respect to White Mountains':

     * growth in book value per share or return on equity;
     * business strategy;









     * financial and operating targets or plans;
     * incurred losses and the adequacy of its loss and loss adjustment
       expense reserves;
     * projections of revenues, income (or loss), earnings (or loss) per share,
       dividends, market share or other financial forecasts; expansion and
       growth of its business and operations; and
     * future capital expenditures.

These statements are based on certain assumptions and analyses made by White
Mountains in light of its experience and perception of historical trends,
current conditions and expected future developments, as well as other factors
believed to be appropriate in the circumstances. However, whether actual
results and developments will conform with its expectations and predictions is
subject to a number of risks and uncertainties that could cause actual results
to differ materially from expectations, including:

     * the failure of White Mountains to complete the acquisition of the Sirius
       International Group or, if White Mountains completes the acquisition,
       its failure to enhance White Mountains' business;
     * the continued availability of capital and financing;
     * general economic, market or business conditions;
     * business opportunities (or lack thereof) that may be presented to it
       and pursued;
     * competitive forces, including the conduct of other property and casualty
       insurers and reinsurers;
     * changes in domestic or foreign laws or regulations applicable to White
       Mountains, its competitors or its clients;
     * an economic downturn or other economic conditions adversely affecting
       its financial position;
     * loss reserves established subsequently proving to have been inadequate;
       and
     * other factors, most of which are beyond White Mountains' control.

Consequently, all of the forward-looking statements made in this press release
are qualified by these cautionary statements, and there can be no assurance
that the actual results or developments anticipated by White Mountains will be
realized or, even if substantially realized, that they will have the expected
consequences to, or effects on, White Mountains or its business or operations.
White Mountains assumes no obligation to update publicly any such
forward-looking statements, whether as a result of new information, future
events or otherwise.