Pressure is mounting on the federal government to split draft laws that bundle welfare cuts with childcare subsidy changes after Pauline Hanson declared One Nation's hand.
The Turnbull government has bundled together 16 welfare cuts, including a reduction to family tax benefits, in an omnibus bill, designed to save billions of dollars that would be redirected into childcare subsidies and disability funding.
The votes of Senator Hanson and her three One Nation colleagues in the Senate were critical to the passage of the legislation.
Senator Hanson overnight killed off the prospects of the bill passing in its present form, declaring the cuts were too hard, too broad and too deep for Australian families.
She urged the government to turn its attention to tax-dodging multinational corporations.
"The coalition needs to realise that before those with the least are asked to tighten their belts, those multinationals with the most, need to start paying their way," Senator Hanson said in a statement.
WATCH: Australians already pay more for childcare than most countries
Welfare groups have painted a bleak picture of the fallout if Australians are forced to absorb $5.6 billion in social security cuts.
"To take even more away from those who are struggling already to live below the poverty line is like feeling like you're lying in the gutter and you've just been kicked in the guts," said St Vincent de Paul Society chief John Falzon.