Under commonwealth law, the federal government can overturn any bid by the Northern Territory or the ACT to give terminally-ill people the right to die.
Australian Greens leader Bob Brown says restoring the rights of future territory governments to introduce euthanasia laws is his top priority.
"This won't bring in euthanasia but it will restore the rights of the Territorians to be able to legislate for euthanasia the same as everybody in the states," Senator Brown told Network Ten on Sunday.
"While this bill is about territory rights, a huge majority of Australians support voluntary euthanasia and it is time for federal parliament to openly debate the issue."
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With the Greens set to have the balance of power in the Senate from July, Ms Gillard has vowed to allow Labor MPs a conscience vote on Senator Brown's private member's bill.
"The Labor Party has previously allowed MPs to express their views on this issue with a conscience vote and if, as a result of these discussions, a conscience vote is called for, there is no reason why MPs would not be afforded this opportunity again," she said in a statement.
But Opposition Leader Tony Abbott said voters had more pressing issues.
"I'm not denying the concerns people have in this area but I think that we need a parliament which focuses on bread-and-butter concerns," he told reporters.
Senator Brown's bill would repeal the 1997 Euthanasia Laws Act.
Federal Liberal MP Kevin Andrews introduced that legislation two years after a conservative Northern Territory government passed the world's first voluntary euthanasia laws.
Four people used the Rights of the Terminally Ill Act to end their lives before the Howard government intervened.
The present Labor administration in the Northern Territory has no plans to re-introduce euthanasia but Chief Minister Paul Henderson was supportive of Senator Brown's bill.
"I absolutely support the right of the Northern Territory Legislative Assembly to determine its own legislation," Mr Henderson said in a statement.
ACT Chief Minister Jon Stanhope, who is personally opposed to euthanasia, said he would be "extremely disappointed" if his federal Labor colleagues voted against the proposal.
"The people of the ACT and the Northern Territory have been treated as second-class citizens," he told reporters in Canberra.
"We haven't been shown the respect that Australians within the states are shown, we don't have the democratic rights."
Former Northern Territory chief minister Marshall Perron, who introduced euthanasia laws in 1995, is backing Senator Brown.
Territorians had "unjustly" been denied the right to decide right-to-die laws for themselves, he said.
A voluntary euthanasia bill was introduced in South Australia's lower house of parliament last week.
Speaking in support, Dr Craig De Vos from the group Christians Supporting Choice for Voluntary Euthanasia said the majority of Christians were in favour of change despite what the church hierarchy said.
"Some people oppose voluntary euthanasia arguing that it's playing God, but so is artificially prolonging life," he said.
Senator Brown first moved the Restoring Territory Rights (Voluntary Euthanasia Legislation) in early 2008.
Northern Territory senator Trish Crossin told AAP she would urge her Labor colleagues to support Senator Brown's bill this time.
