The Federal Government is under pressure to pass new gun smuggling legislation after the ABC revealed a syndicate smuggled more than 130 high-powered handguns into Australia through the post.

Key points: NSW police find major flaws in how customs officials dealt with packages from gun manufacturing nations, four corners reports

NSW police find major flaws in how customs officials dealt with packages from gun manufacturing nations, four corners reports Opposition spokesperson says report provide added pressure for the Government to deal with gun legislation

Opposition spokesperson says report provide added pressure for the Government to deal with gun legislation Justice Minister points out gun smuggling in the ABC's report happened under Labor's watch

Earlier this week, Four Corners revealed a New South Wales police investigation had found major flaws in the way Customs officials dealt with packages from gun manufacturing countries.

Police arrested the men involved in the smuggling syndicate in 2012, while they still had plans to import more pistols.

Following an election commitment, the Coalition introduced a bill earlier this year to set mandatory minimum sentences for gun trafficking, and to increase the maximum sentences from 10 to 20 years in jail.

Opposition spokesperson for justice Clare O'Neil said Labor and the Nick Xenophon Team joined forces to strengthen the bill, boosting the sentence for basic gun smuggling offences to 30 years and also adding more penalties for serious crimes.

She said the Coalition voted for the Bill in the Senate, but it has not been dealt with by the Lower House.

"The only thing standing between these tough new laws and getting gun traffickers put away for life is the Government's unwillingness to bring this back to the House of Representatives, so we're calling on them to prioritise this bill next week," Ms O'Neil said.

"The longer we wait until this incredibly important reform gets through the Parliament, the more people who are caught trafficking in high volumes will be getting what we regard as a slap on the wrist rather than what they deserve — which is serious time behind bars."

Sorry, this video has expired Customs officer delivers gun parts to Botros's post office

Ms O'Neil said the Four Corners report should provide added pressure for the Government to deal with the legislation.

Labor weakened gun bill: Keenan

Sorry, this video has expired Police move in to arrest Andrew Botros

Justice Minister Michael Keenan pointed out that the gun smuggling seen in the ABC's report happened under Labor's watch.

"We need to remind ourselves remind ourselves that the gun importation that was the subject of the Four Corners report was a direct result of Labor's failed border policy," Mr Keenan said.

"When they were in office they cut the budget of customs by three quarters of a billion dollars, and that resulted in a 75 per cent reduction in the screening of cargo as it came into Australia.

"This allowed organised criminal gangs, such as gun smugglers to take advantage of the weakness of Australia's borders at the time."

Sorry, this video has expired Police raided this suspected gang member's home — and found a Glock hidden in a giant teddy bear. Warning: Contains strong language

The minister said Labor weakened the bill by scrapping a proposal for minimum sentences.

"The problem with Labor's approach is it doesn't mean that gun smugglers will actually be getting tougher sentences and that's what we believe the parliament needs to achieve," he said.

When asked whether the Government would bring the legislation on for debate in the Lower House, Mr Keenan said the Coalition would continue trying to convince the Senate to back minimum sentences.