Acting Prime Minister Winston Peters has alleged a cover-up at KiwiRail over the grounding of the Aratere last month.
The troubled Interislander ferry is expected to sail from Picton to Wellington today for the first time since 21 June, under strict safety conditions.
There were allegations from coalition government partner New Zealand First earlier this week the accident last month happened after "someone put the autopilot on, went for a coffee, and then couldn't turn the autopilot off in time when that someone came back".
Party leader Peters this morning appeared to distance himself from the claim, before doubling-down on it.
Asked on RNZ's Morning Report why the party had made the allegation - posted to X (formerly Twitter) on Tuesday - Peters said RNZ would "have to ask the party that".
"But here's the point - at the moment we heard this story, it was clear as daylight that something dramatically had gone wrong, that shouldn't have gone wrong, and we find out it was on autopilot."
Documents sent to staff last week and leaked to the media confirm the ship's autopilot was involved, but said nothing about an inattentive staff member taking a coffee break.
The Aratere departed Picton in line with normal conditions and on time, and as the vessel passed Mabel Island - which is a short way out of the berth - the team switched from hand steering onto autopilot," the document said.
It appeared from that point, a crew member had inadvertently hit an execute button, causing the vessel to alter its course in a way it would do around about one nautical mile further along. As this happened early and steered it towards the shore.
The crew after that point struggled to return it to manual steering mode, and it took around about a minute before the crew was able to apply reverse thrust and have control of the steering - at which point it was too late.
"There's investigations under way, but they've had to be honest and tell us that the allegation made by New Zealand First about the autopilot was in fact true. Now, are you concerned to know that, or are you concerned to have an argument about waiting for a month while they cover their backsides, so to speak?"
"They are responsible to you. You're a taxpayer-owned operation as well. They're required to tell you, the New Zealand public who own them, the truth right here right now. We don't need a month-long inquiry or three or four months while they try and do PR and damage control and cover their butts. Tell us the truth right here right now."
Asked directly if he thought there was a "cover-up" at Interislander operator KiwiRail, Peters said he knew there was.
"I am the acting prime minister, and the reality is that we are wanting to hear the truth, but we don't want to delay any longer. And in a way, you can say I'm asking KiwiRail [to] front up - right here right now."
Merchant Service Guild vice president Iain MacLeod said there was no basis whatsoever to New Zealand First's accusation.
"The vessel had just had two hours in Picton - the bridge crew would have been well-rested prior to departure, and I would be sure they'd have had a coffee in the mess room before doing their pre-departure checks," he told Morning Report.
"So absolutely no basis whatsoever to Nescafe-gate or whatever they called it."
Just why the autopilot was not immediately able to be cancelled "is part of the ongoing investigation", the document said. Maritime New Zealand and the Transport Accident Investigation Commission (TAIC) were running independent probes into the incident, in which no one was injured.
Political response
Labour leader Chris Hipkins was unimpressed with New Zealand First posting the claim to social media, rather than sharing whatever information it had with investigators.
"[New Zealand First leader] Winston Peters is the deputy prime minister in the government, I think he should have a slightly higher standard for himself than that."
He said he had seen no evidence of the claim.
Prime Minister Christopher Luxon, overseas at a NATO conference, said there would be "a lot of stories and rumour around what actually did or didn't happen".
Asked if he was comfortable Peters - the deputy prime minister - had been among those commenting on what might have caused the grounding, Luxon said he had not seen what Peters had said or done, but a process was in place and the government would respond once the reports were completed.
"We have a TAIC investigation up and running and also a Maritime New Zealand investigation up and running. I'll wait to see those formal reports before I pass any comment."
Maritime New Zealand says conditions for Thursday's resumption of sailing include initially carrying crew and rail freight only, with no dangerous goods or passengers, and a tug escort when not in Cook Strait.
