IHTM10376 - Funeral expenses (box 81): overseas funerals of non-domiciled deceased
You should allow overseas funeral expenses as a deduction against the UK estate, even if the deceased was not domiciled in the UK for IHT purposes.
Although IHTA84/S162 (5) might seem to justify the deduction of such expenses from the non-UK estate, that sub-section cannot apply as funeral expenses are not a liability for the purposes of IHTA84/S5 or IHTA84/S162.