IHTM27212 - Foreign property: Property excluded from Inheritance Tax: foreign unsettled property
IHTA84/S6 (1) - ‘Unsettled’ is a term used to describe property which is owned absolutely, and not held in a settlement. Unsettled property that is situated (IHTM27071) abroad at the time it is transferred is excluded property if the beneficial owner (IHTM04031) is also domiciled (IHTM13000) outside the UK at that time.
On the other hand, all unsettled property beneficially owned by someone who is domiciled in the UK is chargeable to IHT, regardless of where it is located.
In any case where the taxpayer or agent claims that the transferor is domiciled abroad at the time of the transfer, you must check to make sure you have all the appropriate information.