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[CARRIER1 LOGO]

                                                                   PRESS RELEASE

             CARRIER1 INTERNATIONAL S.A. ANNOUNCES TENDER OFFER AND
              CONSENT SOLICITATION FOR ALL OF ITS OUTSTANDING NOTES


LUXEMBOURG, 6 NOVEMBER 2001 - CARRIER1 INTERNATIONAL S.A. (the "Company") today
announced that Carrier1 Finance Limited, a wholly owned subsidiary of the
Company, intends to launch a cash tender offer and consent solicitation for
amendments to the indentures (together the "Tender Offer") for all of the
Company's outstanding high yield notes (the "Notes").

The Tender Offer will be conditioned upon the receipt of tenders for more than
50 percent of the principal amount of each of the Company's outstanding Euro
Notes and Dollar Notes taken individually and other standard conditions.

The Company believes that current conditions in the capital markets make it
unlikely that the Company will be able to raise additional capital to refinance
its long-term debt or fund its operations, and the Company believes that it
could experience difficulty in meeting its August 2002 interest payment
obligations on the Notes. The Company's ability to continue to fund its
operations depends on whether it can reduce capital expenditure and costs
significantly, eliminate all or a substantial portion of its debt and conserve
cash required to fund operations until it is cash flow positive. The Company
implemented steps in September 2001 to reduce its costs, including making large
reductions in staff, but does not believe that these steps alone will be
adequate to assure continued funding of its operations.

The Company believes the Tender Offer is in the best interests of the Company
and holders of all its securities, as successful completion will significantly
reduce the Company's indebtedness and interest expense and increase the
Company's chances of being able to continue to fund its operations. The Company
believes that successful completion of the Tender Offer and the adoption of the
proposed amendments to the indentures, which, among other things, will eliminate
or modify certain of the restrictive covenants of the Notes (including certain
restrictions on asset sales, changes of control, mergers and consolidations),
will enhance the Company's financial and operating flexibility as it evaluates
how best to continue to develop its business and pursue strategic opportunities.

Pursuant to the terms of the Tender Offer, bondholders are being offered an
amount in cash as shown below in return for tendering their Notes and providing
their consents.

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                                                             CONSIDERATION PER E1,000 OR $1,000
                                                              OF PRINCIPAL AMOUNT TENDERED(1)
                                                           --------------------------------------
                                                        
HIGH YIELD NOTES
E85mm  13.250% Senior Euro Notes due 2009                            E182.50
$160mm 13.250% Senior Dollar Notes due 2009                          $182.50
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(1) Tendering holders whose Notes are accepted for purchase also will receive
    accrued and unpaid interest up to, but not including, the payment date.

The Tender Offer will expire at 11.59 pm New York City time, on 5 December 2001,
unless extended (such date, as the same may be extended, the "Expiration Date").


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THIRD QUARTER RESULTS ANNOUNCEMENT

The Company expects to announce its results for the quarter ended 30 September
2001 on 14 November 2001. The Company will present its results on a conference
call at that time. Further details regarding that call will be announced in due
course.

DEALER MANAGER

The Dealer Manager for the Tender Offer is Morgan Stanley & Co. International
Limited.

FURTHER INFORMATION

Investors are urged to read the Offers to Purchase and Consent Solicitations
Statement in connection with the Tender Offer distributed by the Company, when
it becomes available, because it contains important information. Investors may
obtain a free copy of the Offers to Purchase and Consent Solicitations
Statement, when it becomes available, by contacting D.F. King, the Information
Agent:

D.F. King & Co., Inc.
77 Water Street
New York, NY 10005 U.S.A.
Attention: Edward McCarthy
Call Toll-Free inside the U.S. (800) 488-8035 (U.S. only) or
outside the U.S.: (212) 493-6952

or

D.F. King (Europe) Ltd.
2 London Wall Buildings
London Wall
London EC2M 5PP
England
Attention: Franklin Stephens
(44) 20 7920-9700


FORWARD LOOKING STATEMENT

This press release does not constitute an offer to purchase the Notes. The
information contained in this press release contains "forward-looking"
statements within the meaning of the U.S. federal securities laws. These
statements can be identified by the use of forward-looking terminology such as
"believes", "expects", "plans", "estimates", "may", "will", "should" or
"anticipates" or the negative thereof or other variations thereon or comparable
terminology, or by discussions of strategy that involve risks, uncertainties and
assumptions.

These statements include, among others, those regarding (i) the Company's
anticipated restructuring and elimination of its debt and the effects thereof,
and (ii) its ability to service its indebtedness and interest expense and its
ability to fund its operations in the absence of such restructuring and
elimination of its debt.

These statements are based on the current expectations of the management of the
Company and performance is subject to risks, uncertainties and other factors
that could cause actual results to differ materially from these statements. Such
risks include but are not limited to: the deterioration of the market economy,
including in Europe and the technology and telecommunications segments; the
deterioration of the financial strength of our customer base; adverse
regulatory, technological, judicial or competitive developments; decline in the
Company's services or products; inability to develop and introduce new
technologies, products and services on a timely basis; pressure on pricing
resulting from competition; unforeseen construction delays and failure to
receive on a timely basis necessary permits or other governmental approvals;
failure to obtain any necessary financing when needed; performance failure by

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third parties with whom the Company has contracted including for the supply or
maintenance of infrastructure components and by joint venture partners; the risk
of termination of certain joint ventures through which the Company operates; the
amount of indebtedness incurred by the Company and its obligations thereunder.

For a more detailed discussion of these risks, uncertainties and other factors
affecting the Company, please refer to the Company's Offers to Purchase and
Consent Solicitations Statement and the Company's prospectus and periodic
reports filed with the U.S. Securities and Exchange Commission on Form 10-K,
10-Q and 8-K, including its Form 10-K for the year ended 31 December 2000 and
its Form 10-Qs for the quarters ended 31 March 2001 and 30 June 2001.
Corresponding filings are available at the Frankfurt Stock Exchange. On or
before 14 November 2001, the Company will file a Form 10-Q for the quarter ended
30 September 2001 with the U.S. Securities and Exchange Commission.

The contents of this document, which have been prepared by and are the sole
responsibility of the Company, have been approved by Morgan Stanley & Co.
International Limited ("MSIL") (which is regulated by The Securities and Futures
Authority Limited) solely for the purposes of section 57 of the Financial
Services Act 1986. MSIL is acting for the Company in connection with the Tender
Offer and no one else and will not be responsible to anyone other than the
Company for providing the protections offered to customers of MSIL nor for
providing advice in relation to the Tender Offer.

                                       END

ABOUT CARRIER1 INTERNATIONAL S.A.
The Company is a provider 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. The Company 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:

CARRIER1 INTERNATIONAL S.A.

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                                                        Alex Schmid
Nicholas Kabcenell                                      Chief Financial Officer
VP - Strategy & M&A                                     +44 20 7001 6000
 +44 20 7001 6000
                                                        E-mail: alex.schmid@carrier1.com
E-mail: nick.kabcenell@carrier1.com




MORGAN STANLEY

Mitch Petrick                                           Ted Doster
Managing Director - Global High Yield Group             Executive Director - Global High Yield Group
Tel: +1-212-761-1558                                    Tel: +1-212-761-1622
E-mail: michael.petrick@morganstanley.com               E-mail: ted.doster@morganstanley.com
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