Prime Minister Jacinda Ardern has delivered her strongest rebuking of NZ First MP and Minister Shane Jones yet, suggesting that if he was a Labour MP, he would face demotion.

She also urged voters to condemn Jones' comments – which have been labelled "racist" and "irresponsible" by the Race Relations Commissioner Meng Foon – and to "act on their values when it comes to election time".

"We are in an election year and that has, I think, driven electioneering out of some of the different parties that are in Parliament – that includes parties in the Government."

Ardern was clearly in damage control mode when speaking to the Indian Weekender this week.

According to her ministerial diary, this was her first sit-down interview with the publication since December 2017.

She was pressed at length on Jones' comments and whether her response was strong enough.

Jones told The Nation last weekend: "I think the number of students that have come from India have ruined many of those [educational] institutions."

Ardern said he was wrong and that she "totally disagreed" with him.

But, speaking to the Herald, Jones said he stood by what he said. His boss, NZ First Leader and Deputy Prime Minister Winston Peters, also backed Jones up, saying he didn't need to apologise.

Speaking to the Indian Weekender, Ardern said she "vehemently" disagreed with Jones' comments.

But asked if the comments were racist, Ardern again would not explicitly say they were.

What she had already said publicly was the "strongest condemnation I could possibly give [Jones'] comments".

She again cited the fact that Jones being in a different party to Labour as the reason why she has not gone further in her reprimand.

"If I had a member within my own party making statements like that, I would have a very obvious ability and course of action that I could take," she said.

"I could demote, I could reprimand; [there is] a range of things that I could do."

But all those things were off the table because – although Jones is one of her ministers – he is in a different political party.

She said voters had an opportunity to stop Jones from making comments like these in the future.

"My message to voters is this: In election year, the power now sits with you. You determine who is able to form Governments and you have it within your power to decide what you make of those remarks, as well," she said.

"What is within other's powers is to join in the condemnation of statements, like those we have seen made by Shane Jones.

"I asked of voters to act on their values when it comes to election time."