-
Sorry, my poor attempt at humour obviously missed the mark: by "Le Gumtree", I meant French Gumtree.
As mentioned above, it looks to have an external BB which suggests it's an English BB.
I did have a UK spec Pug with the ridiculous seatpost diameter, but Decathlon sold a cheap seatpost that came with a suitable shim: I'll see if I can find it.
-
If you should need a new seatpost and it's 24mm:
Unless it's Le Gumtree, you should be fine: Peugeot went over to British standard in the mid-Nineties and even before that, not all their bikes were weird.
Any idea how old it is? Any clues as to whether it made for the French or UK market (labels in French).
Either way, a cheap mixte sounds cheap enough to recycle, rather than repair.