The MID does have the capacity to allow foreign vehicles to be loaded, but there are only a very small  number on there. The police can’t use the data to prevent uninsured driving and it can’t be used to purchase a tax disc since a foreign vehicle will not be registered with DVLA so will not require a tax disc.

If a foreign vehicle is in the UK and intends to stay, it must be re-registered as a UK vehicle within 6 months, and at that point it would be loaded to the MID and treated in the same way as all other UK registered vehicles.