Labor says coalition backbencher George Christensen appears to be running the government, as the conservative MP threatens to quit the party over the backpacker tax.
But cabinet minister Peter Dutton insists his Queensland colleague is a team player.
Mr Christensen told voters in his north Queensland electorate of Dawson he would turn independent if the government didn't back down on plans to scrap tax-free thresholds for working holidaymakers, News Corp reports on Sunday.
"I'm not trying to destabilise but I was that confident such a change will occur that I gave that commitment to locals when I was asked about it before the election," he said.
The revelation comes just days after Mr Christensen and other conservatives on the government backbench claimed credit for changes to superannuation policy.
"Who elected George Christensen? Certainly he got elected in his seat but it appears like he is running the government," Labor frontbencher Penny Wong told ABC TV.
"Malcolm Turnbull might have been elected prime minister but it's very clear, whether you look at superannuation or the backpacker tax ... this is a bloke who is being run by the hard right of the Liberal Party."
But Mr Dutton said the backbenchers were simply trying to achieve the best outcomes for their communities.
"They should be admired for that," he told ABC TV.
"I think George is a team player; our team is working well."
The so-called backpacker tax, due to start on January 1, will slug people on working holiday visas with a 32.5 per cent tax rate from the first dollar they earned, unlike other workers who don't start paying tax until their income exceeds $18,200.
The changes would hit the agricultural sector hard, with about one in four workers on working holiday visas.
The government is holding a review to determine the backpacker tax's fate.
