COLT Telecom Group plc - Blocklisting Interim Review

Market Wire, June, 2005

                            SCHEDULE 5

                   BLOCK LISTING SIX MONTHLY RETURN


To:  Listing Applications
     UK Listing Authority
     Financial Services Authority
     25, The North Colonnade
     Canary Wharf
     London, E14 5HS

AVS No:

               Please ensure the entries on this return are typed

 1.  Name of company  COLT Telecom Group plc

 2.  Name of scheme  COLT Telecom Group Warrants

 3.  Period of return:      From  19.12.2004  to   18.06.2005

 4.  Number and class of share(s) (amount of stock/debt security)      606,999
     not issued under scheme

 5.  Number of shares issued/allotted under scheme during period:            0

 6.  Balance under scheme not yet issued/allotted at end of            606,999
     period

 7.  Number and class of share(s) (amount of stock/debt              9,796,800
     securities) originally listed and the date of admission;       18.06.1997

Please confirm total number of shares in issue at the end of the period in order for us to update our records 1,511,186,506

Contact for queries:                       Address: Beaufort House
Name: Caroline Griffin Pain                15 St. Botolph Street
Telephone: 020 7947 1677                   London EC3A 7QN


Person making return
Name: Caroline Griffin Pain
Position:
Signature:


                      This information is provided by RNS
            The company news service from the London Stock Exchange