How to remove tap cover plate

Anyone know how to remove the cover plates on taps such as these (see linked image)? I have tried prising off with a small screwdriver and hammering a screwdriver inserted at an angle into one of the two holes (thinking the plate might unscrew) but no success and I'm beginning to cause damage to the tap. Do I need a special tool?

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I think they unscrew - very sharp needle nosed pliers?
Pour boiling water over it first to soften goo.

The correct tool is probably a pin spanner - thats a bar with two projecting pins that engage the two holes to unscrew the insert.

A pair of circlip pliers with right angled jaws can sometimes do the deed.