In Attorney-General v De Keyser's Hotel Ltd [1920] AC 508, De Keyser's Hotel was required for use by the War Office during the First World War. When negotiations over the amount of rent to be paid broke down, the Army Council took possession compulsorily, under the Defence of the Realm Regulations, which gave the right to full compensation. However, it was later argued by the Army Council that the seizure of property was alternatively authorised by the prerogative, under which there was no right to full compensation. The House of Lords held that the Defence of the Realm Regulations governing the assessment of compensation must be observed. It reasoned that, assuming the prerogative power in question did in fact exist, the Crown could not simply choose whether to act under that power or under statutory authority. Lord Atkinson summed up the position as follows:

'[W]hen a statute, expressing the will and intention of the King and of the three estates of the realm, is passed, it abridges the Royal Prerogative while it is in force to this extent: that the Crown can only do the particular thing under and in accordance with the statutory provisions, and that its prerogative power to do that thing is in abeyance.'