One Nation should move to ban abortion entirely, Senator Malcolm Roberts has told a Brisbane Christian conference.

His comments are at odds with those of the party’s leader Pauline Hanson, who told the National Press Club on Wednesday it was only “too late to have an abortion” after 20 weeks.

The weekend Church and State summit heard how anti-abortion groups formed an alliance about two years ago to campaign for changes to the law and replace politicians who were not on board.

An audience member asked Roberts why One Nation wasn’t aiming to “get rid of it altogether”.

“That’s becoming my goal,” Roberts said.

“That’s something I’ll be putting to the party. We need to reconsider some things [but] it will be a conscience vote.”

One Nation’s current policy is to “seek every opportunity to roll back brutal and extreme abortion law”. Its new recruit Barnaby Joyce recently spoke at a rally against sex-selective abortion.

Hanson has previously said she is not against abortion in the first trimester, which is up to 12 weeks’ gestation, earlier than the 20 weeks she nominated on Wednesday.

“I’m not against … women that need to have an abortion for medical reasons, for some circumstance,” she said at the press club.

“I’d rather educate women to use contraceptives than to go through an abortion. Too many abortions in this country, anyway.”

One Nation did not respond to a request for policy clarity.

At the weekend summit Roberts said he had learned more about abortion from the Church and State founder, Dave Pellowe, who describes himself as a “writer and speaker on Christian engagement in the public square, specialising in what Almighty God says about complex social issues”.

Roberts was in the front row as Pellowe told the crowd women who committed “child sacrifice” were condemned by God and guilty of murder and that “feminism has had a demonic influence on the culture that has normalised, medicalised, subsidised and industrialised child sacrifice”.

“My job here this morning is not to condemn women who have killed their children, for God already does that,” Pellowe said.

“Every murderer knows they’re guilty of murder.”

Church and State aims to “effectively redeem the culture” by bringing the Gospel into the public square, and specifically into politics. Pellowe has previously spoken about the “long march” to infiltrate political parties “en masse”.

“Let’s end the careers of politicians who want to keep funding the killing of Australians,” Pellowe said on Saturday.

“They must be replaced … There’s an opportunity to repent and be restored and do the right thing every single day. But until you do, you are fired. You’re gone.”

The anti-abortion movement has grown more vocal since abortion was decriminalised in Australia, and since Roe v Wade was overturned in the United States.

There have been multiple legislative attempts to take it out of the healthcare code and put it back in the criminal code.

A recent Queensland bill to stop nurses and midwives prescribing abortion medication was defeated; a sex-selective bill is before the NSW parliament; and a South Australian bill to restrict abortion from 25 weeks was defeated on Wednesday night. While it passed the 22-person upper house with the help of three new One Nation MLCs, it was soundly defeated in the lower house by 36 votes to nine.

The former One Nation MP Sarah Game, who quit in May last year to form the Fair Go party, which she then quit on Tuesday night to join Family First, introduced the bill in the upper house, and the One Nation MP Chantelle Thomas introduced it in the lower house.

The premier, Peter Malinauskas, treasurer Tom Koutsantonis, opposition leader Ashton Hurn, four One Nation MPs, Liberal MP Sam Telfer and Labor MP Michael Brown all voted for the bill.

The Royal Australian and New Zealand College of Obstetricians and Gynaecologists said in a statement that Game’s bill “would eliminate access to abortion in a range of serious and complex circumstances. It also disregards the quality of a woman’s life, including situations where continuation of pregnancy poses significant risks to a person’s physical or mental wellbeing.”

At the summit, Matthew Cliff of the right-wing lobby group Cherish Life said for two years it had been working with the Australian Christian Lobby (ACL), FamilyVoice, the Australian Family Association, Answers in Genesis and the anti-abortion activist Joanna Howe.

“We keep on working, we’re always strategising,” he said.

Cherish Life was “obviously the tip of the spear” of a coalition of anti-abortion groups, ACL’s Rob Norman said.

A press release on the SA bill was issued jointly from Australia Life (Howe’s company with her husband, James Howe) and its subsidiaries BirdFlip and Tradies for Babies, as well as the ACL, Love Australia, Pro-life Health Professionals Australia, the Greek Orthodox Archdiocese of Australia, Family First and FamilyVoice.

The International Women’s Development Agency said on Monday the bills being introduced in various states were “not based in evidence” and “form part of a broader strategy to chip away at reproductive rights and bodily autonomy by introducing incremental barriers to abortion care over time”.