David Cameron's commitment to spend 0.7% of GDP on overseas aid is "nonsense", according to a senior Tory backbencher.
David Davis, who stood against the prime minister in the 2005 leadership election, said the aid budget needed to be more specific.
"Most people when they think about the use of aid broadly approve of it," he told a fringe meeting at the Conservative Party conference in Birmingham on Sunday.
"When it's saving children dying from malaria, when it's saving children from dying from malnutrition, when it is rescuing countries in dire straights."
But the big beast of the backbenches said voters would not understand a generic commitment on aid, particularly when it was given to countries such as India or China.
Cameron has committed to spending 0.7% of Britain's GDP as one plank of his plan to "de-toxify" the Tory brand. However Davis said while the prime minister had been right to "shake off what had gone before", many of his "de-toxifications" had been misguided.
The Haltemprice and Howden MP said rather than focus on issue of overseas aid or gay marriage, which he said was a "distraction", Cameron should make sure Labour was not able to paint the Tories as the party of big business and the rich.