What are the rules surrounding vehicle emissions stickers when driving in France?

I'm told that certain French cities now require cars to display a sticker stating their official emission values. Apparently lots of Brits are being fined by the French cops for failure to comply. Is this true and, if so, what are the rules?

Asked on 27 August 2017 by Petrolhead52

Answered by Honest John
I don't know how many Brits are being fined, but if your car qualifies you need a crit-air sticker to enter Paris, Lyon, Grenoble and Lille. If your car doesn't qualify, you can't even get a crit-air sticker so have to stay out. This explains : www.honestjohn.co.uk/news/miscellaneous/2017-03/mo.../
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