Can an airline deny boarding a passenger if they don’t have a negative COVID-19 test?

Can an airline deny boarding a passenger if they don’t have a negative COVID-19 test?

Airlines must confirm the negative test result for all passengers or documentation of recovery before they board. If a passenger does not provide documentation of a negative test or recovery, or chooses not to take a test, the airline must deny boarding to the passenger. Jan 12, 2021

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