[s1artibartfast]

I think this case is interesting in that it tests the distinction. It isnt a government agency, but it is 100% government owned and provides a public service.

I could see an argument that delivery is not a de jure function of government, but it certainly seems to a de facto function of government.

If a country delegates the execution of it's obligations to a private party, I would expect that it is still responsible for their fulfillment.