AtlasKit form validation - remove valid message

I’m using the Validator component part of the AtlasKit Form component. Looking to remove the success message it displays when the field is valid, and only show the invalid message when it isn’t.

<Validator
    func={() => !!validOrg}
    invalid='Invalid'
    valid='Remove this'
/>

I’ve tried omitting the valid prop, but it defaults to an empty string so you still get the tick icon. I’ve also tried setting it to undefined & null but no joy.

Are there hidden options I’m missing?

Cheers,
George