Jacinda Ardern admits she hasn't yet worked out how to stop foreigners owning New Zealand homes.

One of Labour's election promises was to have a policy by Christmas, to make sure people based overseas can't buy an existing home.

Ardern said the old Government always claimed it would be possible to bring in a stamp duty tax, but she says that would be a breach of free trade agreements.

She said the Government is hoping to finalise a mechanism before the APEC summit in Vietnam on November 11.

"I've been working on that for the last week, and as soon as I've resolved the issue you'll know exactly what it is."

It was a busy morning for Ardern, who had to correct her misspoken ministers. 

She pulled up Transport Minister Phil Twyford for saying any council can ask for a fuel tax, saying Auckland is the priority for the moment.

Now Shane Jones is due for a correction for his comment about being encouraged to look at a work-for-the-dole system.

The Prime Minister told Mike Hosking Labour's focus has always been on readiness for work.

She said working for the dole means working for less than minimum wage.

"In terms of getting people off long-term unemployment, it has the same effect and that is something that both Labour and NZ First agree on and that is we need more active ways of giving people work experience.

LISTEN ABOVE TO PRIME MINISTER JACINDA ARDERN TALK WITH MIKE HOSKING