"I describe him as a wind in the sails," the prime minister told the Nine Network.

"I was treasurer when he was deputy prime minister, Barnaby and I have sat around cabinet tables for years, and we're both passionate about what we want to achieve for this country."

Mr Joyce has already made waves after seizing the leadership in a partyroom ballot, with the Nationals now casting doubt on climate targets and threatening to blow up the Murray-Darling Basin Plan.

The prime minister was challenged on whether the wind Mr Joyce created could prove perilous for the government.

"This is going to get us where we need to go as a country," Mr Morrison said.

"You'll see."

Opposition Leader Anthony Albanese is lapping up the Nationals leadership switch and ensuing policy chaos.

"Spoiler alert: Barnaby is the spoiler," he told a business forum in Canberra on Thursday.

Nationals senator Matt Canavan is proud of the party's water rebellion and pushback on net zero emissions.

However, some of Mr Joyce's recent comments on a Sri Lankan family from Biloela have attracted the ire of a Liberal cabinet colleague.

Immigration Minister Alex Hawke has hit back at the deputy prime minister's "unfair and mischaracterised" claim the government would have treated Tamil children Tharnicaa and Kopika differently if their names were Jane and Sally.

"It doesn't weigh on my mind in any way, shape or form what their names are or what ethnicity they are or what country they've come from," Mr Hawke told SBS.

"It's about whether we owe them protection and whether they fit into our legal migration framework."

Nationals MP George Christensen has announced he will retire at the next election, but there are suggestions he could reconsider now Mr Joyce has returned as leader.

Mr Joyce fuelled the speculation during Question Time on Thursday, heaping praise on the outspoken backbencher.

"I'm doing everything I can to make sure the member for Dawson remains the member for Dawson after the next election because of the advocacy that he has done," he told parliament.

Australian Associated Press