One Nation's first elected lower house MP in federal parliament has warned Australia must be able to stand on its own in a more fragmented world.

Watched on by party leader Pauline Hanson, David Farley gave his maiden speech in the House of Representatives on Tuesday, three months on from his victory at the Farrer by-election.

"The world has become more fragmented, more transactional, more technologically competitive, and more multipolar," he said.

"Australians cannot be blind, dead, arrogant or naive about that change. A sovereign nation must possess the productive capacity to withstand shocks and to survive on its own.

"Sovereignty is more than flying a flag above parliament house. Sovereignty is capacity."

Mr Farley's electoral victory caused political shockwaves, breaking the coalition's 70-year hold on the regional NSW electorate and capping off an ascendancy in the polls of One Nation.

The by-election was triggered by the resignation of former opposition leader Sussan Ley after she was rolled by Angus Taylor for the Liberal leadership.

The One Nation MP used his speech to describe his childhood in the town of Narrendera.

"Language, skin colour or lunchbox content didn't discriminate in the classrooms, the sports field or the school holidays. It moulded us all into the proud, contributing Australians that we are today," he said.

"Nobody owed you promotion. You earned it. Success was achieved beyond hard work."

Mr Farley also called for a re-examination of the Murray Darling Basin Plan, with the electorate being covered by wide tracts of the river system.

"Australia needs the courage to examine the Murray-Darling plan objectively, not ideology, not defensively," he said.

"The greatest test of Australian water policy will not occur during a wet cycle. It will come when the dams empty, the rivers contract."

The 69-year-old said he was not elected to parliament to build a political career, but to represent all of his constituents.

"I've already had a career. I'm here because experience is of little value if we're unwilling to share it and put it to work. "

"The sun may be setting on a passing global era of history, but it does not have to set on Australia. Our task is not to preserve yesterday. Our task is to build tomorrow."