The New Zealand government is understood to have approved a plan to re-enter Pike River mine and will brief families of the mine's 29 victims.

Two Australians, Joshua Ufer and Willie Joynson were among those who died.

NZ Energy Minister Simon Bridges is set to formally announce cabinet's decision on the re-entry plan on Tuesday morning.

Speaking at his post-cabinet press conference on Monday afternoon, NZ Prime Minister John Key did not say which way cabinet had voted on the plan, put up by the families, but said he believes they will be relieved by the decision.

He said there was a lot of discussion, but also consensus, within cabinet on the decision.

Last week the Solid Energy board approved a staged re-entry proposal formulated by families of the victims of the November 2010 explosions with help from experts.

The plan also has be signed off by the Ministry of Business, Innovation and Employment's high hazards unit.

It involves a seal being put in, allowing a team to go 2km up the mine's drift to the point where it collapsed.

It's thought most of the bodies are beyond that point, but families' spokesman Bernie Monk has previously said it's hoped some can be recovered.