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                                   EXHIBIT 12

              CERTIFICATION OF CHIEF EXECUTIVE OFFICER PURSUANT TO
                                 RULE 13A-14(a),
                       AS ADOPTED PURSUANT TO SECTION 302
                        OF THE SARBANES-OXLEY ACT OF 2002

I, Ron F. Hochstein, certify that:

1.    I have reviewed this annual report on Form 20-F of International Uranium
      Corporation.

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 and I are responsible for
      establishing and maintaining disclosure controls and procedures (as
      defined in Exchange Act Rules 13a-15(e) and 15(d)-15e) 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) 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;

      (c) 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 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 the 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 reporting; 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:   December 19, 2005

                                         /s/ Ron F. Hochstein
                                         -------------------------------------
                                         Ron F. Hochstein
                                         President and Chief Executive Officer

                                      F-43
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              CERTIFICATION OF CHIEF FINANCIAL OFFICER PURSUANT TO
                                 RULE 13A-14(a),
                       AS ADOPTED PURSUANT TO SECTION 302
                        OF THE SARBANES-OXLEY ACT OF 2002

I, Mark A. Katsumata, certify that:

1.    I have reviewed this annual report on Form 20-F of International Uranium
      Corporation.

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 and I are responsible for
      establishing and maintaining disclosure controls and procedures (as
      defined in Exchange Act Rules 13a-15(e) and 15(d)-15e) 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) 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;

      (c) 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 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 the 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 reporting; 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:   December 19, 2005

                                    /s/ Mark A. Katsumata
                                    ------------------------------------------
                                    Mark Katsumata
                                    Vice President and Chief Financial Officer

                                      F-44