36 hours after the Prime Minister talked up income tax cuts and the Treasurer has finally come out of hiding to answer questions on the latest tax thought bubble.

In a Government performance reminiscent of the Penrith declaration on state income taxes, Scott Morrison limped through basic questions on morning radio on what exactly the Prime Minister was proposing on income taxes.

Three times Mr Morrison was asked for the details.

SABRA LANE: Okay, why announce it now and when are you looking to deliver these cuts?

SCOTT MORRISON: Well, those details will come when the Government has worked through the details we are currently working through and have been for some time.

SABRA LANE: Okay, let's quantify. What kind of a tax cut are you hoping to deliver? Are you talking about a sandwich and a milkshake tax cut, something that's quite modest?

SCOTT MORRISON: It's too early to be providing those details and I don't intend to do that today.

SABRA LANE: Are you looking to tinker with the thresholds or the tax rates?

SCOTT MORRISON: All of those details will come once the work has been done.

It was hardly the ringing endorsement and backing in of the front page news generated by the Prime Ministers one line or puff of smoke on income tax cuts.

In the same interview this morning, Mr Morrison confirmed that the Government was both increasing income tax while talking about cutting income tax.

Malcolm Turnbull and Scott Morrison havent enjoyed the best of working relationships.

Last year we saw them clash over a GST increase, cuts to income tax, reforming negative gearing, the Penrith declaration on state income taxes and even the date of the Budget!

Yesterday we had the Treasurer in witness protection as the Prime Minister battled to back in his own thought bubble on income tax cuts while today Mr Morrison could not provide any support for the Prime Minister on tax, while confirming that Cabinet had in fact discussed holding a Royal Commission into the banks.

The fact of the matter is that Malcolm Turnbull and Scott Morrison are increasing income taxes for low and middle income Australians not cutting them and Labor will continue to fight against that in the Parliament.