Australian Conservatives leader Cory Bernardi is "deeply concerned" Victoria's euthanasia laws will have negative consequences right across the country.
He understands people's emotional attachment to making the decision to end their own life but when a government endorses such action it is taking a "one-way street".
"It will have massive, long-term changes which are being experienced everywhere in the world. In places like the Netherlands, for example, children can request euthanasia under certain circumstances ... it truly is a slippery slope," Senator Bernardi told Sky News on Sunday.
Victorian federal government MP Tim Wilson said he would oppose any attempt by the Commonwealth to override state law.
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"We're a sovereign state. The state parliament is entitled to make the decisions on these matters," Mr Wilson told ABC TV.
The former human rights commissioner said he had mixed views about the new laws, but gave broad approval for safeguards in the bill which passed on Friday.
"I have always had the view that people should be able to take control of their lives," Mr Wilson said.
"When people are in a situation where they're terminally ill and not in a position to change those circumstances, we have to respect the fact that people may want to end it in a way there is proportionate, measured and sensible.
"But there need to be very strong safeguards."
