A leading auction house which was set to sell a musket once owned by Māori chief Hongi Hika has been targeted with threats.

The item was expected to go under the hammer on May 17 in Auckland at Webb's Auctions. It was estimated to have a potential sale price of up to $150,000.

But the auction has now been put on hold; with the halt being put down to allowing Ngāpuhi the chance to put together an offer to buy it.

At the same time, one historian has raised questions over the item's authenticity.

Hongi Hika, a famous Ngāpuhi war chief was the first Māori to visit Britain and received the firearm as a gift from King George IV in 1820.

It was later handed to Hone Heke in 1828, both prominent leaders in Ngāpuhi history.

Since it was listed for auction, Webb's has received threats about the musket in hopes to have it pulled from the catalogue.

Ngāpuhi board chairman Wane Wharerau told the Herald they did not condone such behaviour.

"We don't want to encourage or generate any further harm," he said.

"If we can get a purchase over the line, I'd much rather do that. Webb's is in a space where they want Ngāpuhi to acquire it."

The Herald initially made Ngāpuhi aware of the pending sale.

The musket was withdrawn from the auction and negotiations are set to happen.

Wharerau went to see the musket for himself at the auction preview yesterday evening before it was withdrawn.

He said a meeting to establish a resolution for all parties is likely, allowing Ngāpuhi a chance to figure out what they can do.

"They want to give us some breathing space to figure out some negotiating."

There are also concerns about its provenance, as the musket was once in Melbourne and Wharerau wants to ensure the musket is authentic.

"I'm curious as to how it got to Melbourne and then back to New Zealand."

Webb's Auctions were not able to say who the current owner of the historic firearm was.

Meanwhile, Radio New Zealand has reported the auction was also pulled after questions were asked about whether the item was authentic.

Historian and military veteran Brent Kerehona Pukepuke-Ahitapu told RNZ that he had researched Hika's 1820 trip to England and has documents from the Royal Archive which he claims describes a different musket to the one being auctioned.

The history of New Zealand's musket wars will be included in Aotearoa New Zealand history curriculum next year.

The musket would have been the first historically significant artefact on the New Zealand market and is only one of many items set to sell for thousands under the hammer.

A pākē (rain cape) which has been in a private collection since the late 1800s is valued between $50,000 and $60,000.

What Webb's describes as "two of the finest pounamu" will also be featured in this catalogue. One said to be an "extremely rare" pounamu breast plate adornment valued up to $22,000.

The much larger and "impressive" pounamu is estimated to be worth up to $35,000.

Both of these items were apparently found by a "deer stalker in a small cave" in the central North Island in the 1950s.

Pounamu can usually only be found in the South Island, hence the island's original name: Te Waipounamu. South Island iwi Ngāi Tahu is the legal kaitiaki of pounamu in the South.