A QUEENSLAND Senator has warned that the defection of his South Australian colleague Cory Bernardi to his one-man Australian Conservatives party must act as a wake-up call to the major political parties, while warning the firebrand senator will enter a "sea of irrelevance".

Nationals Senator Barry O'Sullivan said he considered Mr Bernardi both a friend and a colleague, but that this decision was the wrong one.

He said problems of the party ought to be fixed from within.

READ MORE: Cory Bernardi calls the PM: He's going it alone

The Senator spoke to News Regional Media moments before heading into the Coalition partyroom meeting in Canberra ahead of the first sitting of Parliament for 2017.

The outspoken South Australian -- who won his seat as a Liberal Senator six months ago -- claims the government had lost its way, and its failure to behave as a true conservative party was driving the rise of One Nation and others.

Queensland Nationals Senator Barry O'Sullivan

Senator O'Sullivan conceded that some of the criticisms Mr Bernardi has aimed at the government could not be ignored.

"I think with Trumpism and One Nation, the people are indicating clearly they want us to pay attention to some issues - immigration being front and centre.

"I think there are things that government can do to strengthen up our policies on immigration, and should do."

The Toowoomba Senator described the rise of minor parties, including Pauline Hanson's One Nation and Nick Xenophon Team as the "Uber-isation of politics" in Australia where voters were now rejecting major parties and supporting smaller groups that fit better with their views.

"There's tremendous disruption happening," he said.

"There are some who argue that if a government or a political party doesn't serve their constituency in the matter they want, they'll go and look for something else.

"It's a wake-up call for the major political parties.

"Independents can go out and say whatever they like, they don't have to deliver.

"It's like being a grandparent - you can go out and do whatever you like with the grandkids then hand them back."

"People of One Nation, Jacquie Lambie and others, they cannot deliver on what they've got to say.

"Sure I could go out and tell people what they want to hear too but that would be very irresponsible."

Senator O'Sullivan said after 33 years as a "loyal and dedicated" part of the Nationals in Queensland and now the LNP, he was born that way, and would likely leave this earth the same.