Holding(s) in Company

For filings with the FSA include the                                           
annex                                                                          
                                                                               
For filings with issuer exclude the                                            
annex                                                                          
                                                                               
TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARESi                                
                                                                               
1. Identity of the issuer or the underlying     UNITED UTILITIES GROUP PLC     
issuer                                                                         
of existing shares to which voting rights                                      
are                                                                            
attached: ii                                                                   
                                                                               
2 Reason for the notification (please tick the appropriate box or boxes):      
                                                                               
An acquisition or disposal of voting rights                              Yes   
                                                                               
An acquisition or disposal of qualifying financial instruments which           
may result in the acquisition of shares already issued to which voting         
rights are attached                                                            
                                                                               
An acquisition or disposal of instruments with similar economic effect         
to qualifying financial instruments                                            
                                                                               
An event changing the breakdown of voting rights                               
                                                                               
Other (please                                                                  
specify):                                                                      
                                                                               
3. Full name of person(s) subject to              Deutsche Bank AG             
the                                                                            
notification obligation: iii                                                   
                                                                               
4. Full name of shareholder(s)                                                 
(if different from 3.):iv                                                      
                                                                               
5. Date of the transaction and date                  14/12/2010                
on                                                                             
which the threshold is crossed or                                              
reached: v                                                                     
                                                                               
6. Date on which issuer notified:                    15/12/2010                
                                                                               
7. Threshold(s) that is/are crossed                      3%                    
or                                                                             
reached: vi, vii                                                               

8. Notified details:                                                               
                                                                                   
A: Voting rights attached to shares viii, ix                                       
                                                                                   
Class/type   Situation previous     Resulting situation after the triggering       
of           to the triggering      transaction                                    
shares       transaction                                                           
                                                                                   
             Number     Number      Number     Number of voting     % of voting    
if possible  of         of          of         rights               rights x       
using        Shares     Voting      shares                                         
the ISIN                Rights                                                     
CODE                                           Direct xi  Indirect  Direct Indirect
                                                          xii                      
                                                                                   
GB00B39J2M42 37,928,379 37,928,379  Below 3%    Below 3%  Below 3%  Below  Below 3%
                                                                      3%           
                                                                                   
B: Qualifying Financial Instruments                                                
                                                                                   
Resulting situation after the triggering transaction                               
                                                                                   
Type of financial  Expiration Exercise/           Number of voting    % of voting  
instrument         date xiii  Conversion Period   rights that may be  rights       
                              xiv                 acquired if the                  
                                                  instrument is                    
                                                  exercised/                       
                                                  converted.                       
                                                                                   
C: Financial Instruments with similar economic effect to Qualifying Financial      
Instruments xv, xvi                                                                
                                                                                   
Resulting situation after the triggering transaction                               
                                                                                   
Type of        Exercise Expiration Exercise Number of voting    % of voting rights  
financial      price    date xvii  /       rights instrument   xix, xx             
instrument                         Conversion refers to                               
                                   period                                          
                                   xviii                                           
                                                                                   
                                                               Nominal       Delta 
                                                                                   
Total (A+B+C)                                                                      
                                                                                   
Number of voting rights                Percentage of voting rights                 
                                                                                   
               Below 3%                                 Below 3%                   

9. Chain of controlled undertakings through which the voting rights and/or the 
financial instruments are effectively held, if applicable: xxi                 
                                                                               
Proxy Voting:                                                                  
                                                                               
10. Name of the proxy holder:                                                  
                                                                               
11. Number of voting rights proxy holder will                                  
cease                                                                          
to hold:                                                                       
                                                                               
12. Date on which proxy holder will cease to hold                              
voting rights:                                                                 
                                                                               
                                                                               
13. Additional information:                                                    
                                                                               
14. Contact name:                      Dirk Young                              
                                                                               
15. Contact telephone number:          [phone]