The Australian Electoral Commission has responded to furore over what counts as a valid vote in the upcoming referendum on the Voice to Parliament, following concerns raised by opposition leader Peter Dutton on why a 'cross' won't count as a response.

Discussion sparked after AEC Commissioner Tom Rogers told Sky News earlier this week "it is likely that a tick will be accepted as a formal vote for yes but a cross will not be accepted as a formal vote."

Mr Rogers has said a 'cross' is open to interpretation, that it is hard to discern its meaning and could be considered an indication of approval.

A 'tick' could register as a 'yes' per 'savings provisions' under the Referendum Machinery Act as a clear indication of intent.

Writing 'Yes' or 'No' on the ballot paper, in English, on voting day has been recommended.

On Thursday, 2GB Radio host Ben Fordham labelled the Commissioner's comments "dodgy" before Mr Dutton later joined Rad Hadley on the station to say it was "outrageous" and signal his intent to write to the AEC with his concerns.

"If a tick counts for yes then a cross should count for no," Mr Dutton said.

Mr Dutton also queried whether restrictions made for a "fair process" on Channel Nine's Today program.

Comments were also by sections of the media if the parameters around what counts as a valid response favoured a 'yes' vote.

Education Minister Jason Clare later called the comments from Deputy leader Sussan Ley 'lazy'.

Some noted that Mr Dutton and the Opposition could have raised these concerns during the parliamentary debate of the referendum bill and failed to do so.

On Friday, the AEC released a statement in response to commentary around the topic, describing much of it "factually incorrect" and ignoring aspects of the law.

"The AEC completely and utterly rejects the suggestions by some that by transparently following the established, public and known legislative requirements we are undermining the impartiality and fairness of the referendum," their statement read.

"As has been the case at every electoral event, the AEC remains totally focussed on electoral integrity. Indeed, electoral integrity is a central part of the AEC's published values; underpinned by, and supported through, complete adherence to all relevant laws and regulations."

The AEC clarified 'savings provisions', which they said is lawful and long-held process.

"Legal advice from the Australian Government Solicitor, provided on multiple occasions during the previous three decades, regarding the application of savings provisions to 'ticks' and 'crosses' has been consistent – for decades.

"This is not new, nor a new AEC determination of any kind for the 2023 referendum. The law regarding savings provisions and the principle around a voter's intent has been in place for at least 30 years and 6 referendum questions.

"The longstanding legal advice provides that a cross can be open to interpretation as to whether it denotes approval or disapproval: many people use it daily to indicate approval in checkboxes on forms.

"The legal advice provides that for a single referendum question, a clear 'tick' should be counted as formal and a 'cross' should not.

Mr Rogers had previously told Sky News directives will be clear on voting day.

"We're spending a lot of time talking to the community about what constitutes a valid vote. There'll be very clear information on the ballot paper in the polling place," he said.

"We're spending a lot of time on that issue, and what we're trying to do is to make sure under the legislation that when the voter's intent is clear that those votes are included."

Prime Minister Anthony Albanese is due to announce a date for the referendum next week with October 14 widely speculated as the date landed on.