Exhibit 4.3

FIRST SUPPLEMENTAL INDENTURE        Dated as of April 16, 1991

This First Supplemental Indenture, dated as of April 16, 1991, is between U S WEST Communications, Inc., a Colorado corporation (the "Company"), and
The First National Bank of Chicago, a national banking association duly organized under the laws of the United States of America (the "Trustee").

RECITALS

A.    The
Company and the Trustee have executed and delivered an Indenture dated as of April 15, 1990 (the "Indenture").

B.    Section 9.01
of the Indenture provides that the Company and the Trustee may enter into one or more supplemental indentures without the consent of any
Securityholder for the following purpose, among others: to make any change that does not adversely affect the rights of any Securityholder in any material respect.

C.    Simultaneously
with the delivery of this First Supplemental Indenture, the Company is furnishing to the Trustee an opinion of counsel to the effect that all conditions
precedent to the execution of this First Supplemental Indenture have been complied with.

NOW,
THEREFORE, it is agree as follows:

ARTICLE ONE

Relation to Indenture; Definitions

Section 1.01.    This First Supplemental Indenture constitutes an integral part of the Indenture.

Section 1.02.    For
all purposes of this First Supplemental Indenture:



ARTICLE TWO

Amendment to the Indenture

Section 2.01 of the Indenture is amended to read in its entirety as follows:



ARTICLE THREE

Miscellaneous

Section 3.01.Continued Effectiveness of Indenture.As amended hereby, the Indenture shall continue in
full force and effect.

Section 3.02.Purpose.The purpose of this First Supplemental Indenture is to effect the amendment set
forth herein. The Company warrants that all the conditions and requirements necessary to make this First Supplemental Indenture, when duly executed and delivered, a valid and binding agreement in
accordance with its terms and for the purposes herein expressed, have been performed and fulfilled.

Section 3.03.Rights of Trustee.The Trustee executes this First Supplemental Indenture only on the
condition that it shall have and enjoy with respect thereto all of the rights, duties, and immunities as set forth in the Indenture.

Section 3.04.Counterparts.This First Supplemental Indenture may be executed in any number of
counterparts, each of which shall be an original, but such counterparts shall together constitute but one instrument.



IN
WITNESS WHEREOF, the Company has caused this First Supplemental Indenture to be executed by its Vice President and Treasurer, and its corporate seal to be affixed hereunto and the
same to be attested by its Assistant Secretary; and the Trustee has caused this First Supplemental Indenture to be
executed by one of its Vice Presidents or Trust Officers, and its corporate seal to be affixed hereunto and the same to be attested by one of its Vice Presidents or one of its Trust Officers.

|                                |  | U S WEST Communications, Inc.     
|------------------------------- |  | ----------------------------------
|                                |  | By:                               
|(SEAL)                          |  |                                   
|Attest:                         |  |                                   
|/s/B.M. BELLAssistant Secretary |  |                                   
|                                |  | THE FIRST NATIONAL BANK OF CHICAGO
|                                |  | By:                               
|(SEAL)                          |  |                                   
|Attest:                         |  |                                   
|/s/SHARON MCGRATHTrust Officer  |  |                                   



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