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                       CARRIER1 TERMINATES EXCHANGE OFFER

         NEW YORK, 01-FEBRUARY-2002 - Carrier1 International S.A. (the
"Company") (Neuer Markt: CJN, NASDAQ: CONE) announced today that it is
terminating its offers (together, the "Offers") to purchase for cash and shares
the Company's outstanding 13 1/4% Senior Euro Notes due 2009 and 13 1/4% Senior
Dollar Notes due 2009. The Offers were commenced on January 4, 2002 and were due
to expire this evening at 11.59 p.m. New York City time.

         The Company has been actively pursuing opportunities to enter into a
potential strategic transaction which would enable it to continue to fund its
operations. However, its identified opportunities have recently narrowed. The
Company is considering the options available to it and intends to continue to
discuss the possibility of a strategic transaction with a party which has
expressed an interest in acquiring the Company's business. The Company believes
that at present there is no prospect of it entering into such a transaction
imminently and it is uncertain whether any strategic transaction will be
consummated.

         In addition, since commencing the Offers, the Company's business has
deteriorated. The Company and one of its major customers entered into an
agreement this week to terminate a long-term contract that was under dispute,
resulting in a loss of significant expected revenue. Furthermore, its voice
revenues have declined more than anticipated.

         As at January 29, 2002, the Company had, on a consolidated basis,
approximately $90.7 million of cash and cash equivalents, restricted cash (cash
that is pledged as collateral on outstanding lines and letters of credit and
guarantees to telecommunications companies that provide refile services to the
Company) and available-for-sale securities. A substantial portion of this
amount, however, is held by the Company's operating subsidiaries and is not
available to the Company for the purpose of funding the Offers.

         Due to the Company's financial position as described above, the Company
has determined that it is not permitted by the law of the jurisdiction of its
incorporation (Luxembourg) to issue the shares offered in the Offers because the
Notes do not meet certain valuation requirements under Luxembourg law for the
issuance of shares, as referred to in the Exchange Offers and Consent
Solicitations Statement, dated January 4, 2002, relating to the Offers. As a
result, an essential condition of the Offers cannot now be fulfilled.

         In light of the above factors, the Company has decided to terminate the
Offers.

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ABOUT CARRIER1

Carrier1 International S.A (Neuer Markt: CJN; NASDAQ: CONE) is one of Europe's
top providers of large system solutions for end-to-end Internet, broadband,
voice, data-centre and dialup access communications to large users of
telecommunications services with a network that spans 14,000 contracted route
kilometres in 13 countries, and links 35 European cities. Carrier1 provides its
clients with carrier-grade transport and network solutions as well as
end-user-ready, value-added services that customers then brand and market to
their respective users.

Contacts



Keith Johnson
Carrier1 International SA
 Tel. +44 20 7001 6357
keith.Johnson@carrier1.com


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         FORWARD-LOOKING STATEMENTS

         Some of the statements contained in this release discuss future
expectations or state other forward-looking information, including the
possibility of a strategic transaction and the Company's ability to continue to
fund its operations. Those statements are subject to known and unknown risks,
uncertainties and other factors that could cause the actual situation to differ
materially from those contemplated by the statements. The "forward-looking"
information is based on various factors and was derived using numerous
assumptions. In some cases, these so-called forward-looking statements can be
identified by words like "may", "will", "should", "expects", "plans",
"anticipates", "believes", "estimates", "predicts", "potential" or "continue" or
the negative of those words and other comparable words. These statements only
reflect the prediction of Carrier1. Consequently, such forward-looking
statements should be regarded solely as Carrier1's plans, estimates and beliefs
at the date made. Carrier1 does not undertake, and specifically declines, any
obligation to release publicly the results of any revisions to these
forward-looking statements that may be made to reflect any events or
circumstances that occurred or may occur after the date of such statements or to
reflect the occurrence of anticipated or unanticipated events.