Ford Focus (x reg) judders unless clutch is depressed slightly?

When driving in any gear at any speed my car judders to no end if clutch is released while accelerator is pressed. If both pedals released car is fine but when accelerator is pressed car jols and judders as if its about to stall.

Accelerator and clutch pressed = fine
Accelerator pressed and clutch released = judder
both released = fine

(clutch pressed only slightly… Nothing engages or does anything just a little weight on the peddle is required)

mechanic can find no issue or damage anywhere on vehicle.

From your description it sounds like whatever is causing the vibration is only present when the clutch is either partially or fully engaged (pedal in up position). That indicates an issue with either a contaminate on the pressure plate, clutch disc or flywheel surface, an out of balance clutch assembly or possibly loose connections between the pressure plate and flywheel. The fact that it apparently stops when you place light pressure on the pedal seems to confirm one of the above. I'd start with checking the mounting bolts on the pressure plate.

Hi this sounds like it needs a new engine mount.