Greens and crossbench senators fear Australians could be more vulnerable to terrorist attacks if laws to strip citizenship from dual national terror suspects pass parliament.

Independent senator Nick Xenophon and Greens senator Nick McKim told parliament Australians would be safer if terrorists were locked up in Australia rather than unleashed into the world to do more harm.

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“Will it mean that innocents abroad will have to deal with an extremist, a terrorist, who will spend the rest of their miserable, twisted lives working out how they can kill Australians or other innocents abroad?” Senator Xenophon asked the senate on Tuesday.

In the lower house, Liberal MP Andrew Nikolic called for the bill to go further and suspend citizenship from Australian-born terror suspects.

That would not render them stateless but require them to prove why they should have their citizenship handed back in an immigration court.

“It’s well beyond time we consider suspending citizenship from Australian-born people, not just dual citizens convicted of serious terrorist offences,” he told parliament.

Independent senator Jacquie Lambie wants Attorney-General George Brandis to resign if the proposed laws are successfully challenged in the High Court.