Exhibit 8.1

List of Principal Subsidiaries

The following table sets forth the name and jurisdiction of incorporation of, and our ownership and voting interest (if different) in, our principal operating
subsidiaries and other principal interests as at March 20, 2003.

|Subsidiary                       |                                                 | Country of
incorporation          |                 | Percentage
Ownership
interest
|-------------------------------- | ----------------------------------------------- | --------------------------------- | --------------- | -----------------------------
|KPN Telecom B.V.:                |                                                 | The Netherlands                   |                 | 100.0                        
|                                 |  EuroWeb International Corp.                   |                                   | USA             |                              
|                                 |  KPN Satcom B.V.:                              |                                   | The Netherlands |                              
|                                 |                                                 |  Xantic B.V.                     |                 | The Netherlands              
|                                 |  Ceský Telecom a.s.                            |                                   | Czech Republic  |                              
|                                 |  Infonet Services Corp. Inc.                   |                                   | USA             |                              
|                                 |  PanTel Rt.                                    |                                   | Hungary         |                              
|                                 |  Proclare                                      |                                   | The Netherlands |                              
|KPN Telecommerce B.V.:           |                                                 | The Netherlands                   |                 | 100.0                        
|                                 |  KPN Consumer Internet and Media Services B.V. |                                   | The Netherlands |                              
|                                 |                                                 |  Planet Media Group N.V.         |                 | The Netherlands              
|                                 |                                                 |  XS4ALL Holding B.V.             |                 | The Netherlands              
|                                 |                                                 |  SNT Group N.V.                  |                 | The Netherlands              
|KPN Mobile Holding B.V.          |                                                 | The Netherlands                   |                 | 100.0                        
|                                 |  KPN Mobile N.V.:                              |                                   | The Netherlands |                              
|                                 |                                                 |  KPN Mobile The Netherlands B.V. |                 | The Netherlands              
|                                 |                                                 |  KPN Mobile International B.V.   |                 | The Netherlands              
|                                 |                                                 |  BASE N.V./S.A                   |                 | Belgium                      
|                                 |                                                 |  E-Plus Mobilfunk GmbH & Co.KG   |                 | Germany                      
|                                 |                                                 |  Hutchison 3G UK Holdings Ltd.   |                 | United Kingdom               
|Volker Wessels Netwerk Bouw B.V. |                                                 | The Netherlands                   |                 | 45.0(e)                      
|KPN Vastgoed & Facilities B.V.   |                                                 | The Netherlands                   |                 | 100.0                        

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