What is this Tree

At the bottom of our garden we have the following which we know as a potato plant.
Buy Chilean potato tree Solanum crispum 'Glasnevin': Delivery by Waitrose Garden in association with Crocus
But next to it is a tree which is beginning to take up a lot of room.It was not there when we moved in about eight years ago but has gradually been getting bigger.I have enclosed a copy of pictures of the leaves.Can someone tell me what it is called.Thanks

 

A sycamore, I think, but check against this link: https://www.woodlandtrust.org.uk/visiting-woods/trees-woods-and-wildlife/british-trees/common-non-native-trees/sycamore/

Yours would have arrived as a seed - that link includes a photo of their winged seeds or "keys." Very distinctive, and a very effective means of propagation!

They do grow large and unless your garden is a big one you may want to look into getting rid of it.