The backstop is a clause in the Withdrawal Agreement that says that if at the end of the transition period there's no trade agreement in place which respects the GFA, the UK will remain in a customs union with the EU until such an agreement is reached.
Article XXIV of the GATT has a never used clause which theoretically and with input from the entire WTO Membership, allows Members to implement parts of an almost (but not quite) completed FTA before it's done.
If no satisfactory agreement is reached, the UK, it is argued, could be in a permanent customs union with the EU.
It's an impasse to be sure. Unfortunately, Article XXIV does nothing to help.
The transition period ends without a completed FTA which respects the GFA, but with one within striking distance of completion. Instead of a backstop, the EU and UK jointly notify this almost completed FTA.
If at the end of a transition period an FTA is nearly done then surely the backstop is fine? After all, the objection was to its permanency, not its existence.
If at the end of a transition period the FTA is nowhere near finished, then you can't notify it under Article XXIV anyway. You need a near completed product, not a draft document full of square brackets and opposing red lines.
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