Two Northland MPs and a conservation group are accusing Cabinet Minister Nick Smith of misleading Parliament on the law governing the export of swamp kauri.
Dr Smith was standing in for the Minister for Primary Industries during question-time in the House on Wednesday and fielded questions from the MP for Te Tai Tokerau, Kelvin Davis and New Zealand First leader, Winston Peters.
Conservation groups in the north alleged the Ministry was allowing the export of raw swamp kauri logs and slabs, classed as stumps, carvings and table tops, which they said was contrary to the provisions of the Forests Act.
Mr Peters held up a photo of a large log in the House and asked the Minister why he was saying that such logs were finished products.
"Anyone with half a brain can see they are not," he said.
Dr Smith replied: "The law that was passed defines stumps of kauri including up to four or five metres of the lower portion."
But the Northland MPs said the law said nothing of the sort.
The Forests Act 1949 defined an exportable swamp kauri stump as the root section of the tree, and a portion of trunk from the ground-line, no longer than the tree's diameter.
The act made no mention of lengths of four to five metres.
MPI confirmed to Radio New Zealand earlier this week, that the logs pictured on the website of shipping company Oceanic Navigation were between 4.6 and 5.8 metres long.
The logs weighing up to 40 tonnes each were exported to China in 2013 from Auckland.
While it has provided information about the length of the logs, MPI has so far not supplied further details requested by Radio New Zealand, including inspection certificates, and the name of the exporter.
The Northland MPs said the logs could not have been legal exports, because the diameters of the logs were nowhere near their length.
Kelvin Davis said going by the photos, and the figure of a man standing nearby one of the logs, it was clearly not 4.6 metres in diameter.
"So somewhere along the line the Ministry, or Customs are not doing their job," he said.
The Ministry said the stumps in question included material from above and below ground and the exports were legal.
Radio New Zealand has asked for all the export records held by the Ministry and its contractors relating to the logs - and other shipments of ancient swamp kauri.
The Northland Environmental Protection Society, which has been challenging the Ministry for some years over the way it regulates the export trade, said Nick Smith's comments in the House gave no cause for confidence.
President Fiona Furrell said she believed Dr Smith had either misinterpreted the law, or been poorly advised by MPI officials.
"They possibly believe that [the legality] to be true," she said. "But they really do need to look at the law because what he [Smith] said in the House was completely untrue and from my perspective, misled the House."
Winston Peters and Kelvin Davis agreed.
Mr Peters said the Forests Act was amended in 2004, but its definition of a swamp kauri stump had not changed.
"Mr Smith misinterpreted the law; left out the principal parts of the 2004 amendment legislation, which prohibits the export of logs in the way that he was excusing. He simply got it wrong, and he has misled the House," Mr Peters said.
Winston Peters said there was no need for a moratorium on the export of swamp kauri as some had suggested. He said what was needed was for MPI to enforce the law as parliament had intended.