Do not be naive, if the US negotiators have not already conceded the right of EU airlines to buy into the US airlines in the same conditions as the reverse (look at Virgin Atlantic and Delta) then it will not happen much to our chagrin.
The UK and EU negotiators are appeasers with all the negative implications of that statement. The Open Skies agreement should be called into question and ripped up to be renegotiated if necessary to ensure a level playing field. We are far from that at the moment. Why do we have to kowtow to the US?