Andrew Little has rubbished Winston Peters' claims the Government broke its promise to the Pike River families by giving up on the reentry at the mine's drift.
The New Zealand First leader has filed an affidavit saying the previous Government - of which he was Deputy Prime Minister - committed to going deeper into the mine, where 29 men lost their lives in a series of explosions in November 2010.
The men's bodies are still there after a decade of investigations and conflicting safety advice.
Peters once swore he'd be the first person to go into the mine once it was reopened, but Little - the minister responsible for the re-entry - said he never walked the talk.
"In the three years that I was in Government with him, I invited him many, many times down to the Pike River project, the recovery project he at one point had said he wanted to lead the way in… he never went down," Little told Newshub Nation on Saturday.
"In all the three years of Government, he never went down."
Before the 2017 election Little says Labour, the Greens and United Future signed a pledge to the families to recover the drift - the mine's access tunnel. NZ FIrst didn't.
"Then we formed a Government and Cabinet mandated that the Pike River Agency would be set up to recover the drift - that is very clear in the papers," said Little.
"It's great that Winston's now interested in the project, but before the 2017 election he wasn't. They wouldn't sign the pledge. And he wasn't in the three years we were in Government.
"I don't know if he's trying to rewrite the Cabinet minutes, but the Cabinet minutes are very clear."
Little said they tried going further into the mine, but safety concerns and funding got in the way.
"The more we did, the more we discovered how challenging the project was. We got to 2020 and I needed another top-up, taking it to $51 million. Cabinet was very clear - and Winston Peters was a part of that Cabinet - was very clear 'we have now exhausted our willingness to fund any further activity', and therefore to the extent there was ever any option to go beyond recovery of the drift, that was closed off."
Peters said it was "preposterous" Cabinet would have spent that much money without recovering the bodies.
Hope of recovering the bodies was abandoned in February, but a permanent seal won't go on until the police investigation is over.
"They are doing further work, drilling through the boreholes and putting a scanner down," said Little. "That work will continue for the next few months, then that is pretty much it."
The families are fighting to stop the seal going on.
"I've said it to Mr Little - you've lied to us," spokesperson Bernie Monk told Newshub Nation. "We need people standing up to this Government to make sure they fulfil the obligation they promised the families to do."
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