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                                                                             7
                                                                  EXHIBIT 99.4

                                  CERTIFICATION
            PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, John McLennan, certify that:

1. I have reviewed this annual report on Form 40-F of AT&T Canada Inc.

2. Based on my knowledge, this annual report does not contain any untrue
statement of 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 annual
report;

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

4. The registrant's other certifying officers and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-14 and 15d-14) for the registrant and have:

         a) designed such disclosure controls and procedures to ensure that
material information relating to the registrant, including its consolidated
subsidiaries, is made known to us by others within those entities, particularly
during the period in which this annual report is being prepared;

         b) evaluated the effectiveness of the registrant's disclosure controls
and procedures as of a date within 90 days prior to the filing date of this
annual report (the "Evaluation Date"); and

         c) presented in this annual report our conclusions about the
effectiveness of the disclosure controls and procedure based on our evaluations
as of the Evaluation Date;

5. The registrant's other certifying officers and I have disclosed, based on our
most recent evaluation, to the registrant's auditors and the audit committee of
registrant's board of directors:

         a) all significant deficiencies in the design or operation of internal
controls which could adversely affect the registrant's ability to record,
process, summarize and report financial data and have identified for the
registrant's auditors any material weaknesses in internal controls; and

         b) any fraud, whether or not material, that involves management or
other employees who have a significant role in the registrant's internal
controls; and

6. The registrant's other certifying officer and I have indicated in this annual
report whether or not there were significant changes in internal controls or in
other factors that could significantly affect internal controls subsequent to
the date of our most recent evaluation, including any corrective actions with
regard to significant deficiencies and material weaknesses.

Date:  May 6, 2003

/S/  JOHN McLENNAN
------------------
John McLennan
Vice Chair & Chief Executive Officer


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                                                                              8

                                  CERTIFICATION
            PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, David Lazzarato, certify that:

1. I have reviewed this annual report on Form 40-F of AT&T Canada Inc.

2. Based on my knowledge, this annual report does not contain any untrue
statement of 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 annual
report;

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

4. The registrant's other certifying officers and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-14 and 15d-14) for the registrant and have:

         a) designed such disclosure controls and procedures to ensure that
material information relating to the registrant, including its consolidated
subsidiaries, is made known to us by others within those entities, particularly
during the period in which this annual report is being prepared;

         b) evaluated the effectiveness of the registrant's disclosure controls
and procedures as of a date within 90 days prior to the filing date of this
annual report (the "Evaluation Date"); and

         c) presented in this annual report our conclusions about the
effectiveness of the disclosure controls and procedure based on our evaluations
as of the Evaluation Date;

5. The registrant's other certifying officers and I have disclosed, based on our
most recent evaluation, to the registrant's auditors and the audit committee of
registrant's board of directors:

         a) all significant deficiencies in the design or operation of internal
controls which could adversely affect the registrant's ability to record,
process, summarize and report financial data and have identified for the
registrant's auditors any material weaknesses in internal controls; and

         b) any fraud, whether or not material, that involves management or
other employees who have a significant role in the registrant's internal
controls; and

6. The registrant's other certifying officer and I have indicated in this annual
report whether or not there were significant changes in internal controls or in
other factors that could significantly affect internal controls subsequent to
the date of our most recent evaluation, including any corrective actions with
regard to significant deficiencies and material weaknesses.

Date:  May 6, 2003

/S/  DAVID LAZZARATO
--------------------
David Lazzarato
Executive Vice President & Chief Financial Officer