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My partner has an Indian passport with a Tier 2 general visa and a multi-entry Schengen visa. All websites I've looked at state he doesn't require a visa. We've had verbal confirmation from the Mexican consulate in India and written confirmation from a US consulate that he does not require one. However, the London consulate said they advise one.
We don't have time to get one, is there anything we should take to support entry to the country? Or will he not even be allowed on the flight?