Fairfax Media boss Greg Hywood has told reporters they can be confident that independent journalism will "not just survive but thrive" following a potential merger with Nine Entertainment.
The union representing journalists on Thursday called on the competition watchdog to block the proposed deal - which would create a single $4 billion entity - on the basis media diversity would suffer as a result.
But Mr Hywood told staff in Sydney that Nine management accepted Fairfax journalists worked under a charter of editorial independence.
"That was absolutely embraced and accepted officially by the Nine board last night as they signed off the deal," he said on the floor of the Sydney Morning Herald newsroom.
Mr Hywood said if the deal proceeded "you can all be confident that the culture of independent journalism will not just survive but thrive".
The mastheads would be stronger because they'd be underpinned by a more robust commercial model, he added when urging staff to support the merger.
"That means more opportunity for better journalism."
Mr Hywood has overseen years of cuts at Fairfax but on Thursday quipped: "I'm here announcing my redundancy for a change."
The merged company will be called Nine and be run by current Nine chief executive Hugh Marks.
The Media, Entertainment and Arts Alliance says the "takeover" is the inevitable result of the federal government's "ill-conceived changes to media ownership laws".
"With ongoing inquiries into the independence and long-term viability of quality journalism under way, the ACCC must block this takeover," MEAA media president Marcus Strom said earlier on Thursday.
He subsequently told reporters poor planning by management meant the transition from print to digital news hadn't been coherent.
He warned against cutting jobs in the regions: "If the new entity moves to rationalise or stop regional mastheads they'll have a fight on their hands."
The Australian Competition and Consumer Commission will scrutinise the merger but Hywood and Marks are confident it will proceed.
An ACCC spokesperson said the regulator expects to commence a public review once it's received submissions from Fairfax and Nine.
Mr Strom argues the proposed deal threatens the editorial independence of newsrooms including at Nine, the Sydney Morning Herald, The Age and the Canberra Times.
"It harms the ability of an independent media to scrutinise and investigate the powerful," he said in a statement.
Sydney Morning Herald investigative journalist Kate McClymont acknowledged it was a sad day for those who'd worked under the Fairfax Media banner.
"But I'm not sure our readers actually care who owns us," she told reporters.
"As long as our journalism is good, as long as our investigative journalism still continues to shine a light - I think that's what people care about more than anything."
Fairfax colleague Jacqueline Maley agreed on Twitter stating: "I am less attached (to) the name 'Fairfax' than I am to the names of the noble mastheads we publish ... Hopefully our new overlords will value them too."
