SYDNEY (BLOOMBERG) - Australia will probably head to the polls on May 18 with Prime Minister Scott Morrison expected to wait another week to call a federal election, local media reported on Sunday (April 7).

Mr Morrison has chosen not to visit the governor-general in Canberra on Sunday, AAP reported, a move that effectively ruled out a May 11 election.

Sky News reported that the government had opted against the earlier date due to a number of public holidays that could affect early voting.

The opposition Labor party called that explanation "just absurd".

Labor Member of Parliament Anthony Albanese told Sky News: "The only reason why this is occurring is so that they continue their roll-out of taxpayer-funded advertising."

Mr Albanese said he estimated the ruling Liberal-National government was spending more than A$600,000 (S$578,205) a day on political advertising.

Treasurer Josh Frydenberg declined to say how much money the government was spending on political ads.

"Money is being spent in accordance with approved processes," Mr Frydenberg told ABC's Insiders programme on Sunday. "That's all transparent."

The delay in calling a vote would allow coalition lawmakers to gauge support in the electorate for the federal budget, AAP said.

Mr Morrison's government delivered its budget last week, pledging sweeping tax cuts mostly aimed at the middle class and a spending spree on transport infrastructure.

Polls show the Labor party, led by former union boss Bill Shorten, is poised to win power. Mr Shorten, 51, has promised to implement reforms that would help eliminate generational inequality, skewed by a tax system that Labor claims has unfairly favoured baby boomers.