Pauline Hanson has reportedly claimed that women will get pregnant to access paid parental leave in comments indicating that major changes will be needed to the government’s omnibus welfare bill for it to win One Nation support.

The government faces an increasingly difficult task appeasing Nick Xenophon, who said last week that welfare cuts come at too high a cost, and Hanson, who this week opposed pension cuts but warned that paid parental leave cuts were not deep enough.

On Thursday the Australian reported that Hanson had said there were “some parts” of the omnibus bill she could not support and singled out paid parental leave for criticism.

“They get themselves pregnant and [the government will] have the same problems they did with the baby bonus, with people just doing it for the money,’’ the One Nation leader told the newspaper.

“This is not commonsense ­policy. I’ve gone through a bloody tough life myself as a single ­mother and held down a part-time job. I had no assistance, no help from anyone. But we have such a welfare handout mentality.”

Hanson’s chief of staff, James Ashby, told Guardian Australia that One Nation had not finalised its position in the party room.

“Until that point, [Hanson] is happy to continue talks with the government to make commonsense changes to a number of omnibus measures,” he said.

Senator Malcolm Roberts told Guardian Australia the omnibus bill could have “significant impacts on our constituents and on the nation”, adding that he supported Hanson’s continuing discussions with the government.

The omnibus bill contains $4bn of welfare cuts, including to annual family tax benefits, paid parental leave and the energy supplement for pensioners, and institutes a four-week wait time for unemployment payments for young jobseekers.

Some of the savings will be used to pay for extra funding for childcare and an increase in fortnightly family tax benefit payments.

On paid parental leave, the government proposes increasing the public scheme from 18 to 20 weeks for low-paid women, but cutting the taxpayer-funded entitlement for parents who have employer schemes, limiting it to a “top-up” to a total of 18 weeks.

Labor and the Greens oppose the omnibus bill. To pass it, the government will need the support of both the Nick Xenophon Team and One Nation, which have three senators each. It will also need to win three votes from the rest of the crossbench, consisting of senators Jacqui Lambie, Derryn Hinch, Cory Bernardi; and David Leyonhjelm, who supports the bill.

On Tuesday Hinch told Guardian Australia he would not “cherry pick for the media” which savings measures he supports and opposes. “But I would not pass the complete omnibus bill as it stands,” he said.

Hanson said it was a “lie” that she supported all the savings measures in full. “All I have ever said is I will take a good long look at them and make sure that people are given a fair go,” she said on Twitter on Tuesday.

“The truth is I have only ever called for more help for pensioners and the most vulnerable in our society, while also acknowledging that something must be done about our skyrocketing debt.”

On Thursday it was reported she had said “tough decisions” were needed to fix the budget or else “we will not be able to provide for those in the future who need a helping hand, like the aged, the sick and the needy”.

On 14 February, Xenophon said his party did not oppose every savings measure. “We’re saying that the trade-off, in respect of the family tax benefits and the childcare package, as good as it is, comes at too high a cost,” he said.

“We want to see if there are other savings measures that won’t have that harsh effect on families.”