Populism is undermining Australia as a growing number of politicians ignore the advice of experts, former Treasury secretary Ken Henry has claimed, warning deliberate ignorance is risking the nation's social and economic future.

In stinging comments to a small gathering of MPs and social scientists in Canberra on Tuesday, Dr Henry said governments were claiming success for policies that had not fixed the problem they were developed to confront.

Ken Henry has warned politicians have undermined policy advice, wilfully ignoring experts and risking the economy and the environment. Credit:Dominic Lorrimer

The outgoing chairman of the National Australia Bank said the country faced a string of policy failings that could deprive a large proportion of people of the opportunity to work.

He cited Australia's "truly terrible" broadband service, the deterioration in housing affordability and "extraordinary" low rates of productivity growth that had underpinned "stagnant real wages for several years" as examples of substantial issues that needed to be addressed.