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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,
                                                             ------------------------
                                                                2001           2000
                                                             ---------      ---------
                                                                  (IN THOUSANDS)
<S>                                                          <C>            <C>
Earnings:
   Loss before income taxes                                  $(987,885)     $(108,106)
   Add:
     Interest expense -- net                                   328,675        147,770
     Rental expense representative of interest factor           83,072        110,900
     Minority interest in loss of consolidated
        subsidiaries                                           (19,978)        (9,420)
     Equity losses                                              29,885          9,748
                                                             ---------      ---------
        Total earnings (loss) as adjusted plus fixed
           charges                                           $(566,231)     $ 150,892
                                                             =========      =========
Fixed charges and combined fixed charges and
   preferred stock dividend requirements:
     Interest expense -- net                                 $ 328,675      $ 147,770
     Capitalized interest                                       67,356        116,172
     Rental expense representative of interest factor           83,072        110,900
                                                             ---------      ---------
        Total fixed charges                                    479,103        374,842
     Preferred stock dividends and amortization of
         preferred stock issuance costs                         13,168            540
                                                             ---------      ---------
     Combined fixed charges and preferred stock dividend
         requirements                                        $ 492,271      $ 375,382
                                                             =========      =========
Ratio of earnings to fixed charges                                 (a)            (a)
                                                             =========      =========
Ratio of earnings to combined fixed charges and
   preferred stock dividend requirements                           (b)            (b)
                                                             =========      =========
</TABLE>

(a)  Earnings were inadequate to cover fixed charges by $1,045,334,000 and
     $223,950,000 for the nine months ended September 30, 2001 and 2000,
     respectively.

(b)  Earnings were inadequate to cover combined fixed charges and preferred
     stock dividend requirements by $1,058,502,000 and $224,490,000 for the nine
     months ended September 30, 2001 and 2000, respectively.