A discrepancy in public holiday laws has left New Zealand workers with one less day off than their Australian counterparts this weekend.

The conflicting holiday schedule is due to the fact that Anzac Day and Easter Monday both fall on April 25.

Australian policy is to mark Anzac Day on Monday, and substitute Easter Monday with a public holiday on Tuesday.

In New Zealand both holidays are marked on Monday and workers are made to go back to the office the next day.

Australian Council of Trade Unions assistant secretary Tim Lyons said that was unfair to workers.

His unions had fought hard for internationally competitive leave and holiday entitlements and that was vital to help employees recharge in the modern work environment, he said.

"Australian unions believe workers should not lose public holidays when they fall on a weekend, or coincide with another public holiday such as this year's Easter Monday and Anzac Day.

"Unions believe it is especially important that workers get to mark public holidays given the varying and longer hours they are working.

"If workers do have to work on a public holiday, we believe they should be paid at appropriate public holiday rates."

Australian Department of Commerce spokesman Phil Payne said the Easter Monday holiday had been shifted to Tuesday nationwide so workers were not "robbed" of a public holiday.

"It's simple and readily apparent it is a public holiday and we don't want to deny the community of that."

New Zealand workers also lost their Waitangi Day holiday because it fell on a Sunday this year.

Labour leader Phil Goff said it was unfair Kiwi workers were being deprived of two of their usual 11 public holidays.

His MP Grant Robertson has put forward a member's bill that would "Mondayise" public holidays that fall on weekends.

Kiwis deserved to commemorate national days of significance and get a day off, Mr Robertson said.

Prime Minister John Key has ruled out making any law change, saying both Waitangi Day and ANZAC Day should be celebrated on the date they commemorated.

However, he recently said it was something that could be considered in the future.

Council of Trade Unions (CTU) President Helen Kelly said getting one less public holiday this weekend was indicative of the wider inequalities in how New Zealand and Australian workers are treated.

Australians had better wages, a stronger safety record and more rights, along with the extra holiday, she said.

"There's just a different attitude to working people in Australia.

"Workers are missing out on a significant number of benefits about working in Australia. We've got to enact a whole range of changes around workers rights."

She called on the Government to match the Australian commitment to giving workers holidays for both ANZAC Day and Easter Monday.

"Employers budget for us having 11 holidays and this year they get off lightly."