Australia's governing Liberal-National Party coalition is facing a landslide defeat in the upcoming general election, according to the nation's leading opinion poll.

The latest Newspoll, released on Sunday night, revealed that the coalition trailed the Australian Labor Party (ALP) 44-56 on a two-party preferred basis.

The results indicate that the government's reputation has taken a significant hit following August's leadership crisis that saw Scott Morrison sworn-in as Prime Minister and his predecessor, Malcolm Turnbull, retire from politics.

The Liberal-National Party coalition is the alliance of two center-right parties -- the Liberal Party and the National Party of Australia, commonly known as the Coalition, via which the two parties form the government.

Morrison's performance was overshadowed by that of his government with the ALP set to win as many as 90 of 150 seats in the House of Representatives in the next election, which is due to take place by May 2019, according to the poll of 1,653 voters.

The ALP's primary vote rose to 42 percent, the highest level of support for the party since 2010 and approaching the 43.3 percent that carried the party to a landslide victory in the 2007 election.

It came ahead of Morrison's first parliamentary sitting week as the prime minister where he was expected to lay out his policy agenda regarding economy, power prices and the drought.

Respondents to Newspoll rated energy prices (22 percent), hospitals and aged care (21 percent) and assistance to farmers (21 percent) as Morrison's most pressing issues.

Those who identified as Coalition voters said that the budget deficit was their top priority while ALP voters said it was hospitals and aged care.