Treasurer tight-lipped on tax cut timing

In contrast to his prime minister's flourish in flagging personal income tax cuts, Treasurer Scott Morrison is keeping his cards close to his chest.

Malcolm Turnbull at the weekend said income tax cuts would be announced before the 2019 federal election, but didn't detail when they would come into effect.

Mr Morrison, when repeatedly quizzed during a media conference on Wednesday about putting more meat on the bone, was fairly tight-lipped.

"When I have more to add on the question of tax cuts I will," Mr Morrison told reporters while presenting his response to the latest growth figures.

And they won't be detailed in the mid-year budget review which is due later in December.

Nor would they necessarily be announced in the May budget.

But whenever they do occur, it won't prevent the government returning the budget to surplus as planned by 2021.

"We wouldn't do it otherwise," Mr Morrison said.