Scott Morrison says internal division within the coalition about climate change has been resolved, despite one senator criticising the government's emission targets.
Queensland Nationals senator Matt Canavan said the government's plans for net-zero emissions by 2050 were "dead", despite the coalition agreeing to the plan late last year after much debate.
However, the prime minister said the government supported the climate target.
"Everyone knows that Matt hasn't been supportive of that position, there's no news there," he said.
"That debate has been done in the coalition and is resolved, our policy was set out very clearly, and it has the strong support of the government."
Coalition colleagues on Wednesday were quick to dismiss the senator's comments, with Nationals MPs saying the junior coalition partner was committed to net-zero.
Campaigning alongside the prime minister, Nationals member for Capricornia Michelle Landry told Senator Canavan to toe the party line.
"Pull your head in, Matt," she said. "I agree with the government's position, I'm in one of the biggest coal mining electorates in the country."
Deputy Prime Minister Barnaby Joyce said Senator Canavan was entitled to his climate stance, but the net-zero plan was going ahead.
"My view is that 2050, we made an agreement, we're going to honour that," he said.
"We're going to do our very, very best endeavours to reach the target."
The government has sought to declare Labor's climate policy as being a "sneaky carbon tax" on industries such as mining and transport.
Opposition Leader Anthony Albanese said on Tuesday there would never be a carbon tax under his government.
Both major parties are committed to using the existing safeguard mechanism as the bedrock of their emissions policies.
Shadow treasurer Jim Chalmers said the government was lying about climate as a distraction to coalition division on net-zero.
"This is one of the central issues of this election campaign, and yet the governing party seeking re-election to yet another term can't get its story straight on net-zero by mid-century," he told reporters in Canberra.
"This Liberal-National coalition is hopelessly split on net-zero."
Nationals Senate leader Bridget McKenzie reaffirmed at the National Press Club on Wednesday the government would not be legislating the net zero target.
"We put our plan to Glasgow, we're committed to it, we can't be clearer. Both parties of government in the coalition are absolutely committed to moving to net zero by 2050."
She said the government would "absolutely" continue to support coal-fired power stations.
NSW Nationals MP and former deputy prime minister Michael McCormack said Senator Canavan's comments did not reflect the majority view of the National Party.
"Nats are country people and when country people look you in the eye and shake your hand and say, 'that's a deal', then it's a deal," he told ABC Radio National.
"It doesn't help (election chances). (Senator Canavan) needs to be talking about the good things that we've done."
Climate is resonating as an issue ahead of the May 21 election.
A new survey by Griffith University's Climate Action Beacon found 76 per cent of voters stated climate would be an issue for them at the ballot box.
However the proportion varied across political parties, with 72 per cent of Labor voters saying climate was a key issue while 45 per cent of Liberal Party voters stated it was relevant.