**Exhibit12.1**

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**CERTIFICATION**

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I, Marc Beuls, certify that:

 

1.    I have reviewed this annualreport on Form 20-F of Millicom International Cellular S.A.;

 

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

 

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

 

4.    The company’s other certifyingofficer(s) and I are responsible for establishing and maintainingdisclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and15d-15(e)) and internal control over financial reporting (as defined inExchange Act Rules 13a-15(f) and 15d-15(f)) for the company and have:

 

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

 

(b)         Designed such internalcontrol over financial reporting, or caused such internal control over financialreporting to be designed under our supervision, to provide reasonable assuranceregarding the reliability of financial reporting and the preparation offinancial statements for external purposes in accordance with generallyaccepted accounting principles;

 

(c)          Evaluated theeffectiveness of the company’s disclosure controls and procedures and presentedin this report our conclusions about the effectiveness of the disclosurecontrols and procedures, as of the end of the period covered by this reportbased on such evaluation; and

 

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

 

5.    The company’s othercertifying officer(s) and I have disclosed, based on our most recentevaluation of internal control over financial reporting, to the company’sauditors and the audit committee of the company’s board of directors (orpersons performing the equivalent functions):

 

(a)          All significantdeficiencies and material weaknesses in the design or operation of internalcontrol over financial reporting which are reasonably likely to adverselyaffect the company’s ability to record, process, summarize and report financialinformation; and

 

(b)         Any fraud, whether ornot material, that involves management or other employees who have asignificant role in the company’s internal control over financial reporting.

 
| Date: May 1, 2006 |
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|                   |
| By:                    | /s/ MARC BEULS |   |
|                   | Name: Marc Beuls |
|                   | Title: *Chief Executive Officer* |

 

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