Prime Minister Malcolm Turnbull has accused Labor of creating "policy on the run" amid reports it is about to announce a carve-out for 200,000 pensioners who would feel the pinch from its controversial tax change on dividends.
Labor is keeping its cards close to its chest on any amendment while defending the plan to end cash handouts for non-taxpaying shareholders on their dividend credits, saying the tax office shouldn't be an "ATM for multi-millionaires".
Shadow assistant treasurer Andrew Leigh said it is a unique Australian tax loophole which was originally put in place to avoid double taxation but it is simply isn't sustainable.
He said Labor had consistently fought for pensioners and in government delivered the biggest pension increase in Australian history.
"Labor will always stand up for pensioners, they will always be better off under our government.," Dr Leigh told ABC television on Monday.
But the prime minister says Labor's policy barely lasted a week.
"Bill Shorten can duck and weave as much as he likes. Australians don't trust him with their money. He is coming after pensioners," he told reporters in Canberra.
Treasurer Scott Morrison joined in the attack during parliamentary question time, calling the policy a "dog's breakfast".
"I don't know what is worse, the idiot who put it forward or the idiot who agreed with it," he said pointing at the opposition leader and shadow treasurer Chris Bowen.
Revenue and Financial Services Minister Kelly O'Dwyer also weighed in, describing it as a "granny tax" because it will slug female pensioners over the age of 70 more than any other group of pensioner.
Liberal backbencher Sarah Henderson topically labelled Mr Shorten the ball-tamperer of Australian politics as the Australian cricket team's cheating controversy rages on.
"Bill Shorten is tampering with the accounts of retirees," she told reporters in Canberra..
Even so, Mr Shorten still appears destined for The Lodge when Australia goes to the polls next year.
While the latest Newspoll shows half of Australians are opposed to the opposition's planned change to dividend imputation, Labor's primary vote actually went up to hold a commanding 53-47 point lead over the coalition on a two-party preferred basis.
It was the 29th consecutive poll showing Labor in the lead.
