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Exhibit 10.7

                                                              19 September, 2001

                             TO WHOM IT MAY CONCERN


I hereby retire, and resign with immediate effect from any and all corporate
functions (including as a management or board member, or officer or any other
similar function) which I currently hold with Carrier1 International GmbH or
with any of the entities listed on Appendix A or any other entity directly or
indirectly holding a majority or minority equity interest in ("own") or
controlling, or owned or controlled by, or under common ownership or control
with Carrier1 International GmbH (each a "Carrier1 entity") or any other legal
entity to which I have been nominated or appointed for any such corporate
function by a Carrier1 entity.

I hereby irrevocably appoint each of Tom Zahay, Xavier Dedullen, Alex Schmid and
each member of the board of Carrier1 International S.A., individually, as my
attorney to execute all such documents and to do all such other acts and deeds
as may be required to give full effect to the foregoing paragraph.



/s/ Kees Van Ophem
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Kees van Ophem