Sunrise host Nat Barr has grilled a senior government minister as questions over what responses will count when voters head to the polls for the Voice to parliament referendum later this year rage.

Australians will be asked to clearly write “yes” or “no” on their ballot paper, but Australian Electoral Commissioner Tom Rogers hesitantly conceded this week that provisions allow for a clear tick to be counted as a “yes”, but a cross could not be counted as a “no” due to ambiguity.

The rules have been the same for decades, and the informal vote rate during the 1999 referendum was 0.86 per cent.

But Peter Dutton has written to the AEC demanding a reassessment of the rules, saying that the rules could result in votes being skewed towards the “yes” vote.

Speaking to Education Minister Jason Clare on Friday, Barr asked: “should a cross be accepted as a No vote if the electoral commission is going to accept a tick for the Yes?”

Clare hit back, accusing the Coalition of using the same tactics used in the 1999 republic referendum - noting no one had been confused.

“When John Howard held a referendum with the public, same rules, (it) worked fine, and I believe there were less than one per cent of informal votes,” he said.

“John Howard didn’t want us to become a republic, he was urging people to vote No and these were the rules put in place.

“I think that pricks the bubble of the argument that this is going to cause confusion.”

He said Mr Dutton’s “concern” about potential voter confusion during the Voice referendum was the “weakest, laziest argument” he had ever heard.

Earlier this week, Mr Rogers appeared on Sky News, repeatedly asking voters to just write their response in clear English, saying he was “nervous” of talking about other options, but “savings provisions” existed that allowed AEC staff to count votes that don’t strictly follow the instructions.

“It is likely that a ‘y’ or an ‘n’ would be counted under the savings provisions. But I get nervous even talking about that because then people hear mixed messages. It’s just important to write either yes or no on that ballot paper,” Mr Rogers said.

“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 Dutton said the provisions – which also exist in federal elections – could “skew” the vote against the No campaign.

“Just make it a fair process instead of trying to load the system and try to skew it in favour of the Yes vote,” Mr Dutton told 9 News.

“And I just think that sense of equality in terms of the arguments and people’s ability to make a decision and for it to count and for there not to be a … gerrymander in place.

“I think that is all important so people have some respect for the process, but at the moment, it’s a real problem.”

Under the Referendum (Machinery Provisions) Act 1984 - which the Coalition supported - there is a “savings provision”.

Mr Clare questioned why Mr Dutton hadn’t made his concerns known before the party helped legislate the referendum rules in parliament.

“These are the same rules we’ve had for 30 years and if (deputy Liberal leader) Sussan (Ley) and Peter (Dutton) are so worried about this, why didn’t they move an amendment to legislation a couple of weeks ago when it was going through parliament,” he said.

Mr Dutton wrote to the AEC, asking them to “reconsider” their approach.

“If a tick counts for a yes, a cross should count for no,” he wrote in a letter co-signed with shadow attorney-general Michaelia Cash.

In a statement, the AEC said they “completely and utterly reject” the suggestions that “by transparently following the established, public and known legislative requirements, we are undermining the impartiality and fairness of the referendum”.