The Australian Conservatives party leader Cory Bernardi has publicly invited Tony Abbott to join him, after the prime minister blamed his predecessor for a bad result in the polls.

Government MPs have reacted with rare frankness to the Coalition's worst Newspoll result in two years and nearly all of them are pointing the finger at the former prime minister after his comments last week.

However Mr Bernardi came to Mr Abbott's defence telling Sky News that the former PM was correct.

'What Tony Abbott said the other day was the truth, we need to cut power bills for people, we need to cut government spending, we need to trim our immigration all of the things he spoke about,' he said.

'But for a government minister like Christopher Pyne to come out and say what a catastrophe that the government wants to cut spending, it just says what hope if there the Liberal Party anymore.'

He even invited the backbencher to join him in defecting from the Coalition and joining the

Australian Conservatives party.

'If you're a conservative that thinks governments need to live within their means, and that immigration needs to act within our interest and you're electricity bills are too high, I'm saying come to the warm welcoming embrace of the Australian Conservatives cause that's what we believe in...Tony Abbott included.'

Labor opened a 10-point lead over the Coalition as voters deserted the government for Pauline Hanson's One Nation.

The government's primary vote slumped to 34 per cent, with Labor's trending upwards slightly to sit at 37 per cent.

Prime Minister Malcolm Turnbull said Mr Abbott's 'calculated' critique of the government last week was entirely predictable.

'What we saw was an outburst ... and it had its desired impact on the Newspoll,' he told reporters.

Finance Minister Mathias Cormann, who took Mr Abbott to task last week over his comments, put the result down to the Coalition focusing on itself.

'It's not a surprise after the internal conversation we've had through the media in recent days,' he told ABC radio.

'People mark us down for that.'

Senator Bernardi had a different theory, criticising the government of moving away from its traditional values.

'If you want a centre right government you need to make sure that they have a principled supportive mechanism in the senate, one that is going to uphold the values that typically the traditions liberal voters would have.'

The latest Newspoll coincided with reports a group of conservative Liberal MPs, calling themselves 'the deplorables', sought to undermine Mr Turnbull after last year's close election.

The MPs held regular phone hook-ups which were instigated by Mr Abbott and one of his strongest supporters Senator Eric Abetz, The Australian said.

The pair chaired meetings that included directives to junior MPs to use the media to pressure the Turnbull government on issues such as Safe Schools and amending section 18C of the Racial Discrimination Act.

They also sought to position conservative MPs for a fight over same-sex marriage if Mr Turnbull moved to a free vote once the plebiscite was defeated in parliament, arguing any change of policy would be a leadership issue.

Veteran Liberal MP Warren Entsch hopes Mr Abbott reflects on his time as prime minister as federal parliament resumes in Canberra.

'I would suggest that Mr Abbott reflect on his own period as prime minister before he starts throwing mud at other colleagues. He was actually given a lifeline and he gave himself six months probation and he failed,' he told reporters.

Disaffected voters have pushed Pauline Hanson's One Nation to 10 per cent of the primary vote, more than doubling the minor party's support since November.

With AAP