Overwhelming case for tax reform: Howard

Former prime minister John Howard says there's an overwhelming case for the Turnbull government to raise the GST.

"The argument for the change in the tax mix at some time in the future - and it's a matter for the government to decide when - I think is overwhelming," Mr Howard told The Australian on Saturday.

But Mr Howard concedes there are "medium-term or short-term tactical political considerations" in the decision not to pursue a hike in the consumption tax.