The Senate will on Tuesday debate a private members' bill from Liberal Democrats Senator David Leyonhjelm that would repeal the 21-year-old Andrews Bill, which nullified the Northern Territory's euthanasia laws and stopped the ACT from bringing in a similar scheme.

Senator Seselja said he had no doubt voluntary euthanasia would become law in the ACT if Andrews Bill was scrapped.

"Make no mistake, this is not about territory rights, it’s about human rights. I fear the passage of Senator Leyonhjelm’s Bill will lead to assisted suicide becoming legal in the ACT under a regime that will have minimal safeguards," Senator Seselja said.

"That is, after all, what Senator Leyonhjelm himself has suggested is his intent when arguing that the recent Victorian laws are too restrictive, as they only apply to the terminally ill."

Senator Seselja also accused the ACT government of underfunding palliative care, and suggested it may be easier for governments to pay for euthanasia rather than medical treatment if euthanasia was legalised.

"How’s that for personal autonomy?" Senator Seselja said.

"I will be standing up for the rights of Canberrans to not be pressured to end their lives. I will stand up for proper palliative care.

"I will stand up for the old, the disabled, the sick, the lonely, and all those for whom the passage of assisted suicide would see their lives considered less worthy. I will therefore vote against the Leyonhjelm bill."

It's thought there's enough support in the Senate to pass the Leyonhjelm bill, although the senator has butted heads with Malcolm Turnbull after he allegedly went back on their 2016 deal to allow a free vote in both houses of parliament. Senator Leyonhjelm has threatened to cause havoc if debate in the House of Representatives is blocked.

ACT Labor Senator David Smith has promised to help repeal Andrews Bill, saying he did not believe the territories should be fettered from considering legislation that a state was able to consider and pass.

Former ACT Chief Minister and Liberal party elder Kate Carnell has urged the prime minister to allow the vote to go ahead in the lower house.

Ms Carnell said the ACT had managed to make laws on other conscience issues like abortion, so therefore it could be trusted on euthanasia.

"We run our own hospitals, police, roads and rubbish. We have the capacity to do all of those things so I can't see how we don't have the capacity to make a call on something as important as assisted dying while we manage other difficult issues like abortion," she said.

Ms Carnell said the Leyonhjelm bill and the legalisation of euthanasia in the territories were not mutually inclusive.

"We'll do a whole disservice to the debate if it becomes about who supports assisted dying and who doesn't, it's about the rights of the ACT and the Northern Territory," Ms Carnell said.

However the Canberra Liberals have attacked ACT Chief Minister Andrew Barr over his lobbying with Northern  Territory Chief Minister Michael Gunner to scrap Andrews Bill.

Canberra Liberals leader Alistair Coe said spending taxpayer money to lobby senators on a conscience issue was "reprehensible".

He said the repeal of the bill was a "stepping stone' to legalising voluntary euthanasia in the ACT.

"The reality is the Andrews Bill and the conscience issue of euthanasia are very much intertwined and so just as supporters of euthanasia are doing everything they can to try and get the ACT to bring in euthanasia, opponents will also do everything they can to stop euthanasia from taking place in the ACT," Mr Coe said.

However Mr Barr said the argument was a re-run of the marriage equality debate, in which the Liberals took aim at the government for commissioning rainbow buses ahead of the postal vote at a cost of $22,000.

Mr Barr said the ACT's contribution to the joint campaign with Northern Territory, which included a full-page ad in the Australian on Monday, was around $12,000.

He said recent polling done by government showed 79 per cent of Canberrans surveyed agreed or strongly agreed that the territory should have the right to pass its own legislation on assisted dying.

"What Alistair Coe is arguing is territory residents don’t have the same rights as those who live just across the border in NSW, 15 minutes from where we are now," Mr Barr said.

"If it’s okay in Victoria and it’s okay in NSW why isn’t the ACT able to have this debate?"

Questioned how much scope there was to change minds on an issue of conscience, Mr Barr said "considerable".

"I’ve just come back from Parliament House where I’ve had some further discussions with members of parliament to look to progress [the Leyonhjelm bill] beyond the Senate into the House of Representatives," Mr Barr said.

"There’s people who can only view the issue through the prism of their position on end-of-life issues but there’s quite a lot of people who view it as a territory rights issue."

However Mr Coe said he had come across few people who were against euthanasia, but wanted Andrews Bill spiked.