Ministers have decided to “balance the books on the backs of the starving people of Yemen” in an act that will see tens of thousands die and damage the UK’s global influence, the head of the UN’s Office for Humanitarian Affairs has said.
balance the books = to show that the amount of money a business has received is equal to the amount spent
the "backs of the poor" is an-often used cliché that relates to the labour of poor working people who carried burdens for low pay. As a cliché, it is often used as a metaphor for injustice imposed by others. There are many examples in:
Ernest Gowers expressed the dangers of careless use of cliché:
And almost all writers fall occasionally into the trap of using a metaphor infelicitously. It is worth taking great pains to avoid doing so, because the reader who notices it will deride you. The statesman who said that sections of the population were being “squeezed flat by inflation” was not then in his happiest vein, nor the enthusiastic scientist who announced the discovery of a “virgin field pregnant with possibilities”.2
2 The Deputy Prime Minister not so long ago roundly declared, “We will not balance the books on the backs of the poor.”
The intention of the UN spokesman (who is not the first to do this, there being many other instances as above) is thus commendably to draw attention to the undesirability of ministers' giving priority to financial balance rather than to the misfortunes of the poor. However, the unquestioning use of this cliché also brings up the unintended and diversionary mental image of ministers adjusting the balance of loads of books carried by poor people such as porters. Herein lies the thoughtless ambiguity to which I refer in the question.
This is an example of the importance of saying what you mean and meaning what you say.
Do we have a term that succinctly describes the careless ambiguity of the material in quotes? As it stands it looks like a heartless pun or an unintended double-entendre.