John Key says although he wishes he had a secret Swiss bank account stashed with cash, he "sadly" doesn't.
His admission -- if it can be called that -- comes after Labour leader Andrew Little called on the Prime Minister to release his tax returns, and prove he doesn't have money hidden from the taxman.
Mr Little released his own tax records on Tuesday, but Mr Key has so far refused to do so.
"I follow the rules like everyone else. If they want to change the rules, I'm more than happy to comply -- it wouldn't bother me in the slightest," Mr Key told More FM this morning.
"The rules have to be for everybody -- not just for me because the Labour Party want to concoct some smear campaign."
He suspects even if he did release his personal tax details, critics wouldn't be satisfied.
"They'll say, what about filing the tax return of my family trust? And then they'd say, what about filing the tax return of my blind trust? I don't even know what's in that. It just goes on and on and on."
His UK counterpart David Cameron has had a rough week since the release of the Panama Papers, which revealed how the world's elite hide their money to avoid paying tax.
It's been revealed Mr Cameron's father had money stored in tax havens, and Mr Cameron did too, not selling his share until 2010.
Mr Key says he sent Mr Cameron a text to show "solidarity" with his fellow centre-right leader.
"I've texted him a couple of times just to check he's okay. He's done nothing wrong -- handled it in a clumsy way, but he's admitted that himself."
Tax officials from across the OECD are holding a special meeting in Paris today to discuss the Panama Papers and "explore possibilities of co-operation and information-sharing, identify tax compliance risks and agree collaborative action".