I might me misremembering it, but I think this was told in the documentary Stealing a Nation [1].
According to Wikipedia, there is a commissioner with the Foreign Office that acts as administrator, but that commissioner is directly appointed by the Queen [2].
While this may be technically true, the monarch's powers (the royal prerogatives[0]) are almost exclusively exercised on the advice of the prime minister/cabinet.
In other words, while the power officially rests with the Queen, the UK government is the one to wield it in practice.
