Ms Okin (35) disappeared while walking the Routeburn Track alone on March 26, failing to return to a Queenstown house as arranged to collect her passport and travellers' cheques and other property.
Searchers were back on the track at the weekend but found no sign of the missing woman.
The search was launched last Monday and continued each day last week, with up to 20 police, search and rescue squad members, Department of Conservation rangers, police dogs and up to three helicopters involved.
Ms Okin was last seen at McKenzie hut on the morning of March 26 and was believed to be heading towards Routeburn Falls hut and the Glenorchy end of the track.
The day's walk would have taken her on a zig-zag section of track up through bush to a steep and rocky alpine section, although Acting Senior Sergeant Steve Hutt yesterday said there had been no reported sightings of her on the track that day.
It was possible she had stumbled over a bluff and fallen into an inaccessible area, and it was impossible to cover completely all areas of the search zone because of the difficult terrain, he said.
‘‘It's a nightmare, some of it, and we just can't get people into it,'' he said.
‘‘We are doing everything we can do.''
Two Christchurch-based rabbis from the international Jewish outreach group Chabad-Lubavitch, of Hasidic Judaism, have flown to Queenstown to help liaise with Israeli travellers in New Zealand.
They have been joined by Ms Okin's brother, Itamar Tas.
Snr Sgt Hutt said the police had no immediate plans to abandon the search, and no ‘‘dollar figure'' on how much could be spent. The search would continue until all avenues had been exhausted.
‘‘Once we have exhausted them, it's a different ball game,'' he said. ‘‘At some point, the guys have got to have a rest. It's very long hours.''
