The decision to delay re-entry into the Pike River is supported by the Pike River Families Reference Group.
On Thursday, Recovery Minister Andrew Little announced elevated oxygen levels at the far end of the drift meant that re-entry could not happen on Friday.
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The minister described the elevated levels as "unpredicted and unexplained," and because of this, the mine will not be entered - although there will still be an event for families.
"It's been nearly nine years. Disappointing for the family, I feel for them most. But obviously we're going to prioritise safety first," said Little.
Anna Osborne, who lost her husband, Milton, in the 2010 explosion, said the families were naturally disappointed but understood that health and safety had to come first.
She chairs the Pike River Family Reference Group and spoke with reporters after the announcement alongside Sonya Rockhouse, who lost her son Ben.
"I am actually grateful that the agency are doing the right thing by placing health and safety first to protect those men that want to go in," said Osborne.
"It is not a show-stopper. They will investigate what is causing the issues with the atmosphere and then it will be back on."
Osborne said the management of the mine had played "Russian roulette" with the miners and the recovery agency wouldn't do that with those going in for the re-entry.
"I am incredibly proud of the hard work that the agency have done behind the scenes for so very long. This is only a hiccup."
Little said he couldn't predict when the re-entry would now happen.
"It could be days, could be weeks," he said.
Osborne and Rockhouse were joined by Pike River Recovery Agency chief executive Dave Gawn and chief operating officer Dingy Pattinson.
Gawn and Pattinson agreed with Little that the new date of re-entry was speculative.
They expect to have a greater understanding of the issue and when re-entry could happen next week.