The Department of Prime Minister and Cabinet recorded a sharp increase in spending on consultancy contracts last year, as scrutiny on the government's spending on external advice grows.

While the number of consultancy contracts recorded in the department's annual report grew by 20 per cent, from 104 to 125, the amount spent on the contracts doubled.

Martin Parkinson has said consultants shouldn't be used for "core business" of government. Credit:Dominic Lorrimer

In 2016-17, the department said it spent $3.29 million on consultants, a number that jumped to $7.05 million in 2017-18.

Of that figure, $4.3 million is attributed to 101 new consultancies and $2.74 million to 24 existing consultancies that carried through from the previous year. According to the report there was 104 consultancy contracts in 2016-17 and 111 in 2015-16.