Newspaper journalists have strongly objected to Nine Entertainment hosting a $10,000 a head fundraiser for the Liberal party in Sydney.
Cabinet minister Simon Birmingham, who attended the dinner, said he was grateful to the owners of The Sydney Morning Herald, The Age and The Australian Financial Review for hosting Monday night's event.
"I'm always grateful to those who support the Liberal and National side of politics because those who choose to support it with their vote or with their support in any way, shape or means are ultimately endorsing our policies," Senator Birmingham told Sky News on Tuesday.
The newspaper journalists have written to Nine management saying the event could only serve to make their job more difficult.
"We strongly object to our reputation for independent journalism being compromised by the hosting of party political fundraisers," the house committees of the newspapers wrote to the chief executive Hugh Marks and Chris Janz, the managing director of publishing.
Nine took over Fairfax Media in a $3 billion deal last year.
The journalists said the former Fairfax mastheads had a "long history of political independence".
"If this has changed and we are now associated with the Liberal Party, this should be conveyed to staff."
Senator Birmingham said it was not a matter of Nine endorsing coalition policy or compromising the principles of its journalists.
"I'm just saying it supports us to be able to continue to deliver good policies for Australians," he said.
"Channel Nine can speak for themselves. Their journalists guard their integrity and their independence fearlessly and they do that regardless of what their bosses usually do anywhere around the country."
Nine said in a statement its management and board had been "clear and strong in the support of the charter of editorial independence".
"Editorial impartiality is also integral to the operations of our regulated television business," the statement read.
"We participate actively in our democracy and speak to all parties to press our case around regulation and other political issues that concern our business and the ability of our people to perform their role.
"We took the opportunity last night to present our case to the Liberal party at their business forum and today to the Labor party at their event and dinner with their leader."