The snowshoers reportedly denied visas are Abid Khan and Tanveer Hussain. They were supposed to take part in the 2017 World Snowshoe Championships in New York from February 24-25.
There was no immediate reaction from US Embassy officials who were contacted for comments on the issue.
According to the conversation posted by Rabideau on his page, Khan informed him about the denial of the visa.
"Sorry sir, Visa denied," Mr Khan wrote to the Mayor, a Democrat.
"The lady officer at US embassy in New Delhi after checking all docs (sic), just went inside into another room. After returning she said 'Sorry, due to our current policy we cant issue you visa'," Mr Khan said.
Mr Rabideau, while promising help with the visa, said "this will not stand". The athletes could not be contacted for comments.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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