If it is Not part of your original employment contract and it does not contravene any health and safety regulations then NO they cant enforce it.
Just a note: COVID19, Coronavirus, SARS-COV2 has Never been through the required tests (Koch Postulates) that are used to determine and define it as a virus. Therefore it does not 'officialy' exist, therefore it cannot be legislated against. There are no HS regulations applicable because there are so many exceptions, which I am sure you already know, that it cannot be dangerous.
In fact this virus is so very dangerous, IT CAN BE WASHED AWAY WITH SOAP AND WATER,
It is so dangerous that we are forced to wear masks that are NOT COVID19 compliant. (have a look on your mask box, somewhere it will say that the mask is not a filter for Covid19. They all say this to cover their asses.
Thank for your reply Tamara Veze, I'm not sure where to go to find a definitive answer, this isnt for social care work
In social care -yes the rest -not shore.