The Australian government has been accused of hypocrisy after reports it asked New Zealand to keep open an offer to take 150 asylum seekers.

Malcolm Turnbull's government last year rebuffed repeated offers from Prime Minister Jacinda Ardern to allow detainees being held on Manus Island to be relocated to New Zealand as refugees.

Ardern's persistence briefly caused friction in the Trans-Tasman relationship, with Australian Immigration Minister Peter Dutton saying accepting the offer risked creating a backdoor for people-smugglers.

Barnaby Joyce, then deputy prime minister, suggested New Zealand mind its own business.

But Sky News reports a draft briefing to Ms Ardern released by Immigration NZ reveals the Australian government asked for the offer to be kept open after it was raised in November.

"Australia ... has requested that we keep the offer on the table," the document from November reads.

Australian Labor leader Bill Shorten said it showed the government had been hypocritical.

"It turns out that even though the government bagged Labor for saying Australia should look at the resettlement offer from New Zealand, it turns out behind everyone's back they've been doing exactly that," he told reporters.

Dutton on Thursday said he was pleased the offer was still there.

"We're happy New Zealand has offered the places, leave it on the table. But at this point in time it's not right for us to send people to New Zealand," he told 2GB radio.

He reiterated the New Zealand offer risked being used as a marketing tool by people smugglers.

"And the difference between New Zealand and sending people to somewhere like the United States is New Zealand is the only country in the world that has a visa on arrival status so you can jump on a plane out of Wellington."

The offer to take up the refugees was originally made and left open by Sir John Key's government in 2013.

- NZ Newswire