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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>
                                                         NINE MONTHS ENDED SEPTEMBER 30,
                                                         -------------------------------
                                                              2000            1999
                                                         --------------   --------------
                                                                 (IN THOUSANDS)
<S>                                                       <C>            <C>
Earnings:
   Loss before income taxes and cumulative effect of
     change in accounting principle                       $   (152,000)  $   (248,694)
   Add:
     Interest expense-- net                                    148,205         42,883
     Rental expense representative of interest factor          118,363         51,188
Minority interest in loss of consolidated subsidiaries
                                                               (34,979)       (19,208)
     Equity losses                                               9,748         28,147
                                                          ------------   ------------
        Total earnings (loss) as adjusted plus fixed
           charges                                        $     89,337   $   (145,684)
                                                          ============   ============
Fixed charges and combined fixed charges and preferred
   stock dividend requirements:
     Interest expense-- net                               $    148,205   $     42,883
     Capitalized interest                                      116,172         15,751
     Rental expense representative of interest factor          118,363         51,188
                                                          ------------   ------------
        Total fixed charges                                    382,740        109,822

     Preferred stock dividends and amortization of
         preferred stock issuance costs                            540             --
                                                          ------------   ------------
     Combined fixed charges and preferred stock dividend
         requirements                                     $    383,280   $    109,822
                                                          ============   ============

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 $293,403,000 and
         $255,506,000 for the nine months ended September 30, 2000 and 1999,
         respectively.

(b)      Earnings were inadequate to cover combined fixed charges and preferred
         stock dividend requirements by $293,943,000 and $255,506,000 for the
         nine months ended September 30, 2000 and 1999, respectively.