The Opposition is painting the Prime Minister as being on the side of the rich.

It comes as there has been a fierce debate in Parliament over the Panama Papers, the Government's review of foreign trust laws, and the Prime Minister's connection to a firm that specialises in foreign trusts.

SEE ALSO: Key refuses to cut ties with lawyer over foreign trust link

Labour Leader Andrew Little said everyone has thought John Key is this easy-going, charming, affable, man of the people - but he's not.

He said we know who his friends are, who he associates with, and who he takes his advice from.

"And it is those who live in that world of enormous [...] mega wealth who will do everything they can to avoid their civil obligation, to avoid paying the taxes that they should pay."

But the Government is hitting back, saying the Labour leader has got his facts wrong.

Revenue Minister Michael Woodhouse said Mr Little is either being obtuse about the issue or is banging on about things that aren't true.

He cited comments Mr Little has made about foreigners hiding their wealth here.

"There's no wealth hidden in New Zealand with these foreign trusts. Otherwise, here's the thing, they wouldn't be foreign - they would be domestic trusts."

Meanwhile, New Zealand First Leader Winston Peters is stepping up his attacks on the man chosen by the Government to review foreign trust laws.

Mr Peters has highlighted John Shewan's role as an advisor to Westpac during its legal proceedings with IRD that resulted is an over $2.2 billion out of court settlement.

He has asked why Mr Shewan was chosen to do the review and said it's not because he's a poacher turned gamekeeper.

"No, he's the poacher out to help poachers, and he will not change. Mr Key, you see, couldn't get an independent expert because he cannot stand the sunlight of disclosure, and that's what this is all about."

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