Barnaby Joyce has warned government infighting is "not a good look" as Malcolm Turnbull and Tony Abbott trade public blows over power prices.
The prime minister took a thinly-veiled swipe at his predecessor during Question Time on Monday, saying there must be an end to "ideology and idiocy" over energy policy.
Mr Abbott returned fire just hours later, saying "idiocy is doing more of the same and expecting a different result".
Mr Joyce, who fell out with the prime minister earlier this year after having an affair with a staffer, counselled the duelling pair during a press conference in Canberra.
The former deputy prime minister suggested it would be good for Liberal Party unity if Mr Abbott was given a cabinet position.
"I would like, as much as possible, to keep everyone together," he told reporters at Parliament House on Tuesday.
"I think that would be a smart move as we go into an election year (but) I am not a fool, I think the chances of that are like zero."
Mr Joyce said ministers were bound by cabinet solidarity, but backbenchers could raise concerns about policy.
"If you don't speak your mind in a democracy, then what are you doing?"
As a divided coalition thrashes out its energy policy, an emboldened Bill Shorten has taken strength from positive polls to accuse Mr Turnbull of belittling voters.
The Labor leader welcomed back three MPs and introduced another new one to caucus after four successful by-elections over the winter break.
The latest YouGov/Galaxy poll, published in The Courier-Mail, shows the government's hopes of holding its 21 Queensland seats are slipping.
The major parties are now locked at 50-50 on a two-party-preferred basis, after the LNP was ahead 52-48 in May.
Another new Essential poll also has Labor ahead 52-48 on the national two-party preferred vote.
Mr Shorten took aim at disunity in the coalition over energy and Mr Turnbull's attitude to voters who "got it wrong" in the by-elections.
"That performance should have sent a shiver down the spine of every marginal seat government member," he told the Labor caucus on Tuesday.
Mr Shorten also seized on the government's National Energy Guarantee, which is causing angst among climate sceptics in the Liberal and National parties.
"For five years, the current Liberal government has said that they will bring down power prices and, in fact, power prices have gone up," he said.
