8Where the Board are satisfied that in any territory outside the United Kingdom any amount of tax chargeable by reason of any disposition or other event is attributable to the value of any property situated in that territory, then, if that tax is of a character similar to that of capital transfer tax or is chargeable on or by reference to death or gifts inter vivos and any capital transfer tax chargeable by reference to the same disposition or other event is also attributable to the value of that property, they shall allow a sum equal to the first-mentioned amount as a credit against that capital transfer tax.