**Exhibit  12.1**

----

 

**CERTIFICATION**

I, Bernardus  Johannes Maria Verwaayen, certify that:

|  | 1. | I have reviewed this      annual report on Form 20-F of BT Group plc; |
|--|----|-----------------------------------------------------------------------|

|  |   |                                                                                                                                                                                                                                                                                                                           |
|--|--------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|  | 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 15d-15(e)) and internal control over financial reporting (as defined      in Exchange Act Rules 13a-15(f) and 15d-15(f)) 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)     | Designed such internal      control over financial reporting, or caused such internal control over financial      reporting to be designed under our supervision, to provide reasonable assurance      regarding the reliability of financial reporting and the preparation of      financial statements for external purposes in accordance with generally      accepted accounting principles; |

|  |   |   |   |                                                                                                                                                                                                                                                                                                       |
|--|--------|--------|--------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|  |   |   | 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 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      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: May 14,  2008

| /s/ Ben      Verwaayen                                              |   |
|---------------------------------------------------------------------|--------|
|                                                                     |   |
| Name: Bernardus Johannes      Maria VerwaayenTitle: Chief Executive |   |

 

----