Thanks Monica and Jarno, appreciate you taking the time to give your opinions.
Completely agree with what you have said. There are obviously many multinational businesses so I cant see why Google will have an issue with having multiple sites (even pointing at each other) as long as it provides value, firstly to the visitor in terms of trust and also as a trust signal to Google (assisting them provide more reliable results.) In my mind the advantages far out-way the "potential risk". On the flip side doing it to manipulate ranking, purely to pass link juice or replicating and re-purposing content across multiple sites could have a negative impact but I don think that applies in this case.
Will do some more research and see whether webmaster support has posts on dealing with multinational brand sites.
Thanks again!