What is this???

What is this???

Observation - What is this??? - UK and Ireland. Description: I found this wasp type thing in my garden, strolling round a bucket containing vegetable matter. I have searched extensively online for a similar image but to no avail. Is it a wasp?? I've never seen one like it before or since.

I found this wasp type thing in my garden, strolling round a bucket containing vegetable matter. I have searched extensively online for a similar image but to no avail.
Is it a wasp?? I've never seen one like it before or since.