Winston Peters no shoo-in for Pike River ministry - Labour

Winston Peters won't automatically become Minister for Pike River if he sides with Labour, the party's deputy leader has said.

Mr Peters is expected to announce whether he's going with National or the Labour-Green bloc by Thursday, five days after the final results of the election are announced on Saturday.

The NZ First leader has made a manned re-entry into the Pike River mine one of his bottom lines, and met with the victims' families on Thursday to reiterate that pledge. When asked on The AM Show if it was the best day they've had since that fateful day in 2010, Anna Osborne responded "hell yes".

"After nearly seven years of fighting, we've had so many hurdles we've had to jump to get where we are today. It certainly put a smile on my face and a lot of the Pike River families' faces as well. It was one of the best days."

Ms Osborne lost her husband Milton in the disaster. She says unreleased images and footage shows many of the bodies of the 29 men killed in the explosion are intact and recoverable.

"They aren't all ash, like some Government ministers had led the public to believe."

While Labour and the Greens have pledged to do what they can to retrieve the bodies, it's been Mr Peters who has stood strongest with the families for the longest time.

"He will very much lead the charge for re-entry into the drift of Pike River," said Ms Osborne.

But that doesn't mean he'll automatically be put in charge of any potential manned re-entry if he sides with Labour and the Greens.

"I'm not going to into the negotiations now," Labour deputy leader Kelvin Davis told The AM Show. "The person will be decided in time."

National deputy leader Paula Bennett, also appearing on The AM Show, said National wasn't opposed to a manned re-entry as long as it was safe.

"I'm a politician - it's not my job to be ascertaining whether or not there are the right gases and right airflow in there for people to be able to do that kind of entry."

Prime Minister Bill English earlier this year said Mr Peters' plan to exempt a manned re-entry from health and safety laws would put lives in danger, and Environment Minister Nick Smith called it a "hollow political stunt".

"We're certainly not planning on changing the law to satisfy Winston Peters," Mr English said in May.

Ms Bennett said however with technology improving in the seven years since the disaster, it could perhaps be done.

"We're not anti the re-entry at all, it's just a matter of making sure there's no future loss of life."

The families have had a number of experts determine it can be done safely, but so far the Government's sided with experts with the opposing view.

A Solid Energy robot is expected to re-enter the mine by the year's end.