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                                                                      EXHIBIT 12

                       WILLIAMS COMMUNICATIONS GROUP, INC.

               COMPUTATIONS OF RATIO OF EARNINGS TO FIXED CHARGES
               AND RATIO OF EARNINGS TO COMBINED FIXED CHARGES AND
                      PREFERRED STOCK DIVIDEND REQUIREMENTS


<TABLE>
<CAPTION>
                                                           THREE MONTHS ENDED
                                                                MARCH 31,
                                                        ------------------------
                                                           2001          2000
                                                        ----------    ----------
                                                             (In thousands)
<S>                                                     <C>           <C>
Earnings:
  Loss before income taxes                              $ (259,104)   $  (76,794)
  Add:
     Interest expense -- net                                82,483        51,383
     Rental expense representative of interest factor       30,895        32,010
     Minority interest in loss of consolidated
       subsidiaries                                         (6,608)       (4,500)
     Equity losses                                           5,901         3,067
                                                        ----------    ----------
       Total earnings (loss) as adjusted plus fixed
         charges                                        $ (146,433)   $    5,166
                                                        ==========    ==========
Fixed charges and combined fixed charges and
  preferred stock dividend requirements:
     Interest expense -- net                            $   82,483    $   51,383
     Capitalized interest                                   34,019        28,444
     Rental expense representative of interest factor       30,895        32,010
                                                        ----------    ----------
       Total fixed charges                                 147,397       111,837

     Preferred stock dividends and amortization of
       preferred stock issuance costs                        4,416            --
                                                        ----------    ----------
     Combined fixed charges and preferred stock
       dividend requirements                            $  151,813    $  111,837
                                                        ==========    ==========
Ratio of earnings to fixed charges                             (a)           (a)
                                                        ==========    ==========
Ratio of earnings to combined fixed charges and
  preferred stock dividend requirements                        (b)           (b)
                                                        ==========    ==========
</TABLE>

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(a)  Earnings were inadequate to cover fixed charges by $293,830,000 and
     $106,671,000 for the three months ended March 31, 2001 and 2000,
     respectively.

(b)  Earnings were inadequate to cover combined fixed charges and preferred
     stock dividend requirements by $298,246,000 and $106,671,000 for the three
     months ended March 31, 2001 and 2000, respectively.