CANBERRA - The Australian government is still trailing the Opposition before May's general election, a poll has revealed.

According to Newspoll, one of the nation's most respected opinion polls, the opposition Australian Labor Party (ALP) leads the governing Liberal-National Party Coalition (LNP) 54-46 on a two-party preferred basis, extending the ALP's lead from 53-47 in the previous poll.

It represents the 50th consecutive Newspoll loss for the LNP under the leadership of two prime ministers.

The poll is a blow for the government and Prime Minister Scott Morrison, who has begun his re-election campaign by attacking opposition leader Bill Shorten's national security and economic credentials.

The ALP has promised to increase Australia's refugee intake, ambitious renewable energy and emissions reduction targets and a far-reaching tax-and-spend economic agenda.

The LNP is relying on a message of stability, saying it is the party best-equipped to manage the nation's economy.