Political commentators have questioned the recent tax claims made by Labour leader Chris Hipkins during his State of the Nation speech - claiming most will hear the speech and question why the party did nothing about the issues whilst in power.

However, Hipkins told Mike Hosking Breakfast this morning that his government wasn't able to do "a lot of things" as the Covid-19 pandemic required the bulk of his Parliament's attention.

Delivering his speech on Sunday, Hipkins said that now is the time to have the tax debate, despite Labour ruling out both a wealth tax and a capital gains tax last year. He pledged to spend the next two years releasing discussion documents, to get them best prepared for the next election.

Hipkins said it was something that needed to be taken more seriously, especially when the IMF speaks out.

"The reality is, salary and wage earners are shouldering a disproportionate share of the tax take, and we should be making sure that it's more evenly balanced."

However, Newstalk ZB political editor Jason Walls told the Mike Hosking Breakfast he wasn't entirely sure why the Labour leader was coming out swinging about the country's tax system, given it was an issue that cost his party during the election.

Walls said Labour had been accused of coming up with something ham-fisted in a knee-jerk reaction to the last election.

"Tax has really hampered the Labour Party, and I think the problem the party is going to have going forward is anything they come up with, they'll be asked the obvious question of 'why didn't you do this before?'."

"The party had a historic majority to do things in the house with tax, and they chose not to do that. So it makes things - like Hipkins getting up and talking about tax, or Robertson saying what he wishes he could have done something around tax - it really renders that argument a little bit redundant."

Walls also played devil's advocate, and suggested that if Labour came out with any policies so recently after the election's conclusion, the party would be criticised for coming up with things too early in their campaign.

"So, Hipkins saying we need to have a conversation about tax is probably the only thing they could have done yesterday."

Hosking asked Walls where Labour stood on discussions of wealth tax and capital gains taxes, considering the party was divided on the issue during the last election. Walls said certain people who were in favour of both taxes were still involved with the party.

An example was David Parker, who Walls said has "kept his head down" during the election but was still playing a big role for the party behind the scenes.

"I think a lot of questions have to be asked about the new finance spokesperson, Barbara Edmonds, who in the past seems to have been in favour of [both taxes], and revenue spokesperson, Deborah Russell, we know certainly is."

Later in the morning, the Labour leader spoke with Hosking about his speech and defended his speech - stating that New Zealand was an international outlier compared with the way other countries handled their tax.

He said the current tax system had problems and that more New Zealanders could see this was the case.

"Fewer and fewer people, as a proportion of the workforce are going to be earning PAYE and income tax from salary and wages, so we are going to have to look at the fact we don't have any form of CGT," he said.

"The International Monetary Fund has said our tax system needs to be reformed, I think it is about time we took a good look at it."

Hosking told Hipkins his party had come out of three years of an historic singular majority elected through the MMP system and had done nothing about the tax issues he was raising, to which Hipkins suggested there was good reason.

"There were lots of things we didn't necessarily do in that three year period, we were also dealing with a global pandemic which of course consumed a huge amount of time and energy from the leading Government, and we won't have that going forward," he said.

Hipkins said his party hasn't decided on a proper solution to the tax issues, he said he's identified the problem and will now oversee opposition researching the best options to fix the problem and decide on the best approach.

He said his intention was to release a proposal for the country's tax system "well before the next election" to give the country time to digest their plan, he then took a jab at the way the National Party had released their plan.

"I'm not going to do what the National Party did and drop my tax policy weeks before the election so that all the holes in it don't get poked apart."

When asked how much of Labour's approach to opposition was simply plotting its path back to power and allowing time to take its toll on the current coalition Government, Hipkins said both would happen and called the current Government "a shambles".

He said the public could already see cracks beginning to show, but that he wanted his party to look different to the one that didn't attract votes last year.

"I've said I want us to be the best-prepared opposition going into a general election, ready for Government compared to any other opposition in New Zealand's history," he told Hosking.

"I think that means we need policies that are implementable, that we've done all the numbers on...it's going to be quite important for the public to see that."