I don’t think that it’s sustainable for the EU to say (if that’s what it is saying) that COVID subsidies *granted by the EU* don’t fall under the subsidy control provisions of the UK FTA while equivalent UK subsidies do. https://twitter.com/tconnellyrte/status/1340195090820706306
I don’t follow the “it would require a change in the Treaties” line: the EU is competent to enter into trade agreements that impose international obligations on it not to exercise Treaty powers in certain ways. Eg GATT.
Nor do I understand the “we can’t allow the UK to block us” line. All that is being proposed is that the UK could impose tariffs (subject to any arbitration/conciliation) mechanism if it objects to what the EU is doing.
To coin a phrase, the EU’s sovereignty is not infringed just because a third country can take action if it doesn’t like what the EU is doing.
If the EU wants to be free to grant COVID aid without risking UK retaliation, then a better course would be to allow the UK a mirror exemption from retaliation, applying to all subsidies that fall within the EU scheme.
NB that the UK concern about this reflects an important truth: it is in the UK’s interests to have some ability to respond to EU subsidies - subsidy control is (or ought to be) a UK offensive, and not just a defensive interest.
And standard disclaimer: all commentary on what is being discussed is looking through a glass darkly.