(39)It should be possible for a depositary to delegate the safe-keeping of assets to a third party which, in its turn, should be able to delegate that function. However, delegation and sub-delegation should be objectively justified and subject to strict requirements in relation to the suitability of the third party entrusted with the delegated function, and in relation to the due skill, care and diligence that the depositary should employ to select, appoint and review that third party.