Can a disbeliever be regarded as a mahram for his Muslim sister when travelling?

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Check below answers in case you are looking for other related questions:
Who are the mahrams in front of whom a woman can uncover?
Should she go with her mother for ‘Umrah without a mahram or stay at home on her own?

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Related Answers:
Ruling on bringing a servant without a mahram
Did the wives of the Prophet (peace and blessings of Allaah be upon him) perform Hajj without a mahram?
Taking a female servant for Hajj with no mahram for her
Who are the mahrams in front of whom a woman can uncover?
Should she go with her mother for ‘Umrah without a mahram or stay at home on her own?

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