Can anybody help me identify this plant and advise me when to prune it?

Many thanks for your help

Mike

Maybe a Viburnum.

https://en.wikipedia.org/wiki/...

Many thanks for your help with this. I think you're right.

Mike

Welcome, Mike!

Viburnums have opposite leaf arrangement, your plant has alternate leaf arrangement. Viburnum also have terminal flowers (and thus, fruit) at the ends of branches. Yours does not. Sorry, but I don't know what it is.
And I would suppose your location is London, England? (Not any of the many Londons in the USA or other countries?)

Okay, Why is this identified? All we know is what it isn't.

Is it a shrub, or does it perhaps have tendrils and climb like a vine? My eyesight isn't great but my first thought was Vitis (Grape) of some sort.

It looks like a currant (Ribes) to me. I wonder if it could be Ribes bracteosum based on the colour of the fruits:

https://www.google.ca/search?q...: