Brexit: Flu vaccine 'could be airlifted into UK'
Hugo Fry, the managing director of its UK arm, told BBC Radio 5 live's Wake Up To Money that the flu vaccine was one it was not possible to stockpile.
"We prepare in different ways and have prepared many different routes into the UK," he said.
"If we have to in the end, we will airlift it in."
He added: "We are eating the cost of that but patients and citizens are our primary concern, so we're quite happy to take that cost and make that planning."
Health Secretary Matt Hancock said: "Those sorts of medicines can be flown in and we have plans for that. I pay tribute to Sanofi and other pharmaceutical companies - they have done an enormous amount of work to make sure people will be safe and medicines can flow.
"In the health department we don't use the word guarantee, as this is a complex system and there are lots of levers beyond our control such as how the French government responds on the Dover/Calais border.
"However, Sanofi have done a tremendous amount of work to ensure people can get their drugs unhindered and if necessary we'll fly them in."
Sanofi says it is the second biggest of three suppliers of flu vaccines in the UK - behind Seqirus and ahead of Mylan.
While Sanofi has plans to keep stockpiles of insulin and vaccines in place for 12 months, Mr Fry said this was not possible with the flu vaccine.
"You can't stockpile it because it's made at a particular time of the year and it's only available to import in the month at the end of August/beginning of September," he said.
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