Act Party leader David Seymour has been denounced for a joke he made saying he would "close the door" on New Zealand First leader Winston Peters if he re-entered Pike River mine.

During his election campaign, Mr Peters has repeatedly insisted he would only work with a Government which stuck to several 'bottom lines' - including manned re-entry into the Pike River mine.

So far, he has nine 'bottom lines':

Keeping the retirement age at 65

Holding binding referenda on 100 MPs in Parliament and on abolishing on Maori seats

Building a Northland rail link

Manned Pike River re-entry

1800 more police

Rebuilding the Christ Church Cathedral

Changing the Reserve Bank Act

And holding a referendum on smacking.

The Government says Mr Peters might need extra assistance to keep track of his promises.

"I suspect he's going to have to employ someone to follow him around and remind him of his bottom lines," Finance Minister Steven Joyce told Newshub.

But he found an unlikely ally for at least one of them:

"Re-entry of Pike River is one I agree with, I'll be there to close the door after him," Mr Seymour told Newshub.

Manned re-entry into the mine has remained controversial, with the Government saying it's too dangerous to send people back in.

And Mr Seymour's joke hasn't gone over quite as well as he may have hoped.

"He's such a creep! Insensitive idiot thinks he's being clever and funny," user @leahlava tweeted.