The likelyhood is female Sparrowhawk but the photo does make it look big even without perspective.
Less likely to be a Goshawk as has been said but strange things happen in bird watching.
Some years ago we saw an Alpine Chough near Holyhead. Many of the experts said it wasn't possible. Then 3 weeks later someone got a photo of it.
Similarly, years ago we had a Parakeet land on our bird feeder and I got good photos of it......the first recorded sighting in the North West.
Nice spot though
@doughnut