A bill voted down in senate last night would have allowed the ACT and Northern Territory to legislate on the issue of voluntary euthanasia, something they have been banned from doing since 1997.

The senate saw 34 votes versus 36. One of ACT’s voluntary euthanasia supporters, Labor MLA Tara Cheyne, blamed the fail on ACT Liberal senator Zed Seselja, who voted no.

"Make no mistake, I will never let Zed or any voter in the ACT forget where he stood on this issue of our rights," she said.

ACT Chief Minister Andrew Barr said supporters faced a setback but would continue to agitate for change.