The Turnbull government and Labor remain at loggerheads over a push to impose compulsory jail terms for gun traffickers.
Both sides used parliament on Wednesday to accuse each other of playing politics over the issue, casting doubt on the future of the proposal.
The coalition used its numbers in the lower house to reinstate mandatory minimum sentences in a package of draft firearms laws, having been removed in the Senate - where it will now head back.
Labor, the Greens and crossbenchers joined forces in February to amend the legislation in the upper house to create new aggravated offences for firearms trafficking attracting penalties of 30 years' jail or life for the worst offenders.
Labor's justice spokeswoman Clare O'Neil accused the government of playing "petty politics at its lowest form" with gun safety.
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She wants the bill to be split to allow the other measures - which have bipartisan support - to sail through instead of sending parliament into deadlock.
The opposition doesn't agree with mandatory sentencing because it takes away the discretionary powers given to judges to appropriately sentence criminals.
But Justice Minister Michael Keenan insists compulsory jail time would act as the strongest possible deterrent to gun-related crime and violence.
He said Labor's vote against mandatory minimum sentencing "is a vote in support of criminals".
"Unfortunately, Labor has put politics ahead of public safety and opposed the coalition's tough crackdown on gun smugglers," he said in a statement.
