I actually liked the UK's reaction to that: we don't obey your rulings, get stuffed.
It's not as if Mauritius has any legitimate claim to those islands either. It is ridiculous that Mauritious is claiming different inlands more than 2000km away because at one point they were administered as part of the same colonial domain. It
would be similarly ridiculous to claim "self-determination" for a small archipelago that could not possibly be self-sufficient in any way. This was just Mauritius' government doing a land grab. It takes a lot of gall to claim those islands because "self-determination" while at the same time offering to sell other islands to
India. Apparently self-determination can be ceasing to be part of the British Empire and becoming part of an Indian Empire.
And this is not even getting into the issue of politics within Mauritius, and Indioa's repeated meddling there...