The government's proposed new workplace safety laws are ready to be debated again in parliament.
But that won't happen until Wednesday, prompting Labour to accuse the government of "running scared".
The Health and Safety Reform Bill's committee stage was originally scheduled to begin tonight and families of men killed in the Pike River mine disaster and other workplace accidents travelled to Wellington to be at parliament for the clause-by-clause debate of the bill.
Workplace Relations and Safety Minister Michael Woodhouse says the bill is "ready to go" and the delay was because he was talking to the government's support parties - ACT, United Future and the Maori Party - about "a couple of technical matters".
He denies there was anything tactical about it.
Labour leader Andrew Little doesn't buy that.
"I think they are running scared," he told reporters.
"They are internally divided. They don't know what to do and they've got families here reminding the government of their commitments and indeed their moral obligation to all families in New Zealand to make sure we have the best possible health and safety laws."
The health and safety reforms, which were promised in the aftermath of Pike River, have been delayed a number of times.
The bill was changed after it was introduced following complaints to National Party MPs from small businesses and farmers who thought it would saddle them with unnecessary costs and legal obligations.
The government says it has "struck the right balance" but opposition parties say the legislation has been seriously weakened.
One of their main complaints is that the bill now makes it voluntary for low-risk businesses with fewer than 20 employees to have elected health and safety representatives.
The previous intention was that all businesses should have them.
The committee stage is the only stage at which a bill can be changed.
Opposition parties are going to put up a raft of amendments, but to succeed with any of them they need the support of at least one of the government's allies ACT and United Future.