From Backwoodsman's link:
Currently, a driver of a UK-registered car is allowed to drive anywhere in the EU, the EEA (European Economic Area), Switzerland and Serbia, and not have to carry a green card that proves you have insurance cover.

But if the UK leaves without a deal, all changes and drivers will be expected to carry a green card when in mainland Europe and Ireland. They are likely to be issued by an insurance company for free, but the industry is warning it could take up to a month to obtain one, so if no deal happens and you're booked to go away with the car this Easter, you will need to act fast.

Typical Guardian: But if the UK leaves without a deal, all changes and drivers will be expected to carry a green card when in mainland Europe and Ireland. That sentence makes no sense (except to Guardian readers). I'm guessing that there should be a word, or phrase, between 'all' and 'changes'. But in the absence of such, it makes no sense.

The second paragraph says that drivers will be 'expected to carry a green card'. This does NOT mean that they will be 'required' to carry one. Again, Guardian readers may have a different understanding of the English language.

I know that there are those here who think that quoting from The Guardian helps put their case forward, but it appears that those who write for that paper are lacking in their understanding of the English language.