These white flowered plants are better known as Hoary Mock Oranges due to the similarity in the flowers appearance to the flowers of the citrus tree. The plants are native to the Eastern united states but efforts have been made to internationalise it, hence my coming across it in the midlands of the UK.
The flower is perennial, so when I came across it in October I was too late to see the white flowers the plant is known for, instead I only have a picture of the leaf, but the plant can still be identified from this.
Map
Below shows a map of every location where I have come across this plant:
