Inspector Mark O'Connor said no date had been confirmed for the handover yet, but it would not happen this week.
"The parties involved are taking the time to ensure we get a seamless transition that will focus on safety and planning ahead,” he said.
“There are process issues to be worked through that are not related to the ongoing work to monitor the mine."
Police Commissioner Howard Broad announced the handover three weeks ago.
PricewaterhouseCoopers submitted its mine stabilisation plan to the police four days later.
Engineering, Printing and Manufacturing Union national secretary Andrew Little told ILN the handover was previously anticipated to occur over the weekend.
Recovery operation progress
Despite uncertainties over the timing of the handover, there has been steady progress with the recovery operation at the mine.
The expensive-to-run GAG jet engine is on standby, giving its crews a well-deserved break.
Shotcrete is around the GAG componentry in the access portal to prevent oxygen from entering the mine.
A New Zealand Police spokesperson told ILN the mine had not been “officially sealed” but crews were “constantly going back and sealing any cracks” which appeared.
A portable Floxal inertisation unit is pumping nitrogen underground to inert the underground atmosphere and lower temperatures in the mine.
The spokesperson could not verify whether the nitrogen generator was pumping the gas through one of the drilled boreholes or through the slimline ventilation shaft.
Borehole 47 was recently completed and images taken underground are being analysed.
Another borehole was 20 metres away from holing into the mine as of yesterday.
The main purpose of the additional boreholes is to get a better range of gas samples.
The spokesperson said the difficult terrain limited where boreholes could be drilled, especially into the general area where the first explosion is thought to have taken place.
Underground gas reading were “looking good and trending down slightly”.
The Floxal inertisation unit is a 500 cubic metre per hour system, while 2000cu.m/h systems are used in Australian longwall mines to inertise goaf areas.
Another portable Floxal unit is steadily cooling temperatures at the Blakefield South longwall mine in New South Wales, where there was an underground fire last month.
