The group believes both methods could potentially satisfy safety and technical criteria, but more work is required before a deciding is preferable.

“Progress is being made, but there is more work to do,” the group said in a statement.

“Work on both methods will proceed in parallel.

“Once there is general agreement about the preferred option, further work will be needed on various elements to firm the plan up. Then it will be reviewed by the High Hazards Unit, as safety is paramount, and then ministers will consider it.

“The government has indicated it is prepared to fund a safe, technically feasible and financially credible drift exploration project if one is developed.”

There will be an update once decisions have been taken at the end of the process. However, there will be no detailed comment from working group members while this process is going on, it said.

Pike families met with representatives from the government High Hazards Unit, Solid Energy and the Mines Rescue Trust in Christchurch on Tuesday to determine whether there was a safe and technically feasible way to access the 2.3km tunnel within the Pike River mine.

Prime Minister John Key indicated he would consider government funding for the mine re-entry as the financial position of the mine’s new owner, Solid Energy, deteriorates.

Solid Energy continues to struggle despite a number of initiatives to cut costs, preserve cash and restructure the business to meet the ongoing challenging global coal market.