People employed by the ABC and SBS will be exempted from the definition of Commonwealth officers, while relevant security classifications will be defined as the "secret" and "top secret" levels.

The journalists' union had sought a full exemption from the law for reporters while media companies including News Corp, the ABC and Fairfax Media - publisher of The Australian Financial Review - said the plan risked criminalising the media's work.

Last month, after taking over from former attorney-general George Brandis, Mr Porter conceded there had been confusion about the plan but said blanket exemptions for professionals or other groups would not be workable.

Opposition Leader Bill Shorten called on the government to fix mistakes with the plan, warning Labor would not support laws that saw journalists imprisoned for doing their jobs.

Mr Porter said he believed the changes struck the right balance between keeping Australians safe amid a range of serious international threats and not impeding the work of journalists and media organisations.

"The bill is the next stage in a five year process of modernising our national security laws which is absolutely vital to protect Australians. Safeguarding Australia's national security will always remain the Turnbull government's number one priority.

"There has been no intention to unnecessarily restrict appropriate freedoms of the media. Where drafting improvements are identified that strike a better balance, the government will promote those changes," Mr Porter said.

The government hopes for bi-partisan support for the proposed laws and said more changes to the legislation could come as a result of the committee process

"There is a strong history of bipartisan support for national security legislation in Australia and I would hope that these amendments which ensure media freedoms, whilst maintaining the bill's integrity to protect Australians and the sovereignty of our democratic institutions, will also secure bipartisan backing," Mr Porter said.

Prime Minister Malcolm Turnbull has described the proposed laws as "the most important overhaul of the nation's counterintelligence framework since the 1970s".