John Key is sounding uncomfortable over the Panama Papers dump when it comes to New Zealand's role as a tax haven.

He's gone from denying anything is an issue last week to hedging when pushed by Mike Hosking today.

"The advice we get is that New Zealand has full disclosure, has a good regime and is doing things professionally. But if there are changes that need to be made, government will make them."

Key's defending New Zealand being used as a tax haven, saying there are good reasons to keep money in offshore accounts.

He told Mike Hosking New Zealand allows some people to do so, because some reasons, are valid.

"Ah, there are legitimate reasons to have a foreign trust in a country, and it could be all sorts of reasons. You believe you're going to be persecuted, you just don't trust the system you're in, you believe there's corruption in the system."

Having initially rebuffing calls for an inquiry into New Zealand's role, the Prime Minister has this morning buckled.

He said the government will commission an independent expert to look into the matter.

MORE: David Cameron publishes his tax records

There have been more international ripples from the Panama Papers, with Malta the latest country to call on two senior Cabinet ministers to quit over their financial arrangements.

One of them - Health and Energy Minister Konrad Mizzi, set up a company in Panama and has a trust in New Zealand.