The latest Newspoll, conducted for The Australian, released on Sunday night, shows Mr Morrison's personal approval has risen by two points to 68 per cent with his dissatisfaction rating falling by the same amount to 27 per cent.

But the coalition's primary vote is unchanged at 42 per cent, with the party maintaining a 51-49 lead in the two-party preferred vote.

Voters in Eden-Monaro will go to the polls on Saturday for a by-election triggered by the resignation of former Labor MP Mike Kelly because of ill health.

Internal Nationals polling shows the party's vote in Eden-Monaro has nearly doubled from six to 11.5 per cent in the past two weeks, increasing the Liberal Party's chances of picking up the seat, The Australian reported.

Meanwhile the Newspoll showed Labor's primary vote support at federal level has risen slightly, by one point to 35 per cent, despite a branch-stacking scandal engulfing Victorian Labor.

Mr Morrison's net approval rating is the highest since he became leader in August 2018, and the highest of any prime minister since the early period of Kevin Rudd's leadership, since the Newspoll began in the 1980s.

He has increased his margin over Anthony Albanese as preferred prime minister, lifting two points to 58 per cent.

Mr Albanese was unchanged 26 per cent, while sixteen per cent of voters didn't back either leader.

Support for the Greens has dropped one point to 11 per cent, as did voter backing of Pauline Hanson's One Nation, which also fell a point to three per cent.

The poll, which surveyed 1521 voters, was conducted from June 24-27.

Australian Associated Press