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                                                                    EXHIBIT 12.1

                                 CERTIFICATION

I, Michael Diekmann, certify that:

     1. I have reviewed this annual report on Form 20-F of Allianz
Aktiengesellschaft;

     2. Based on my knowledge, this report does not contain any untrue statement
of a material fact or omit to state a material fact necessary to make the
statements made, in light of the circumstances under which such statements were
made, not misleading with respect to the period covered by this report;

     3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and cash flows of the company as of,
and for, the periods presented in this report;

     4. The company's other certifying officer(s) and I, are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) for the company and have:

          (a) Designed such disclosure controls and procedures, or caused such
     disclosure controls and procedures to be designed under our supervision, to
     ensure that material information relating to the company, including its
     consolidated subsidiaries, is made known to us by others within those
     entities, particularly during the period in which this report is being
     prepared;

          (b) [Omitted in accordance with the guidance of SEC Release No.
     33-8238]

          (c) Evaluated the effectiveness of the company's disclosure controls
     and procedures and presented in this report our conclusions about the
     effectiveness of the disclosure controls and procedures, as of the end of
     the period covered by this report based on such evaluation; and

          (d) Disclosed in this report any change in the company's internal
     control over financial reporting that occurred during the period covered by
     the annual report that has materially affected, or is reasonably likely to
     materially affect, the company's internal control over financial reporting;
     and

     5. The company's other certifying officer(s) and I have disclosed, based on
our most recent evaluation of internal control over financial reporting, to the
company's auditors and the audit committee of company's board of directors (or
persons performing the equivalent functions):

          (a) All significant deficiencies and material weaknesses in the design
     or operation of internal control over financial reporting which are
     reasonably likely to adversely affect the company's ability to record,
     process, summarize and report financial information; and

          (b) Any fraud, whether or not material, that involves management or
     other employees who have a significant role in the company's internal
     control over financial reporting.

Date: July 15, 2004

                                          /s/ MICHAEL DIEKMANN
                                          --------------------------------------
                                          Michael Diekmann
                                          Chief Executive Officer