Search teams have spent a second day in the Haast River area looking for missing Canadians Connor Hayes, 25, and Joanna Lam, 24.
The pair were last seen at Fox Glacier last Tuesday, before their rental van was hurled down a remote gorge in a landslide.
The vehicle was found smashed to pieces at the bottom of an 80 metre gorge on the Haast Past, which was battered by heavy rain and landslides during a massive storm last week.
A fuel tank belonging to the wrecked campervan was found washed up on a coastal beach about 50km from where the vehicle left the road, and helicopters yesterday spotted one of the van's seats.
Police said the van was likely pushed into the gorge by a landslide on State Highway 6, which remains closed by another, huge slip nearby.
A helicopter with heat-seeking equipment helped in the search today, as well as a specialist search dog on the ground.
West Coast Area Commander Inspector John Canning has conceded that chances of finding the pair alive are extremely remote.
"Our effort now is a recovery operation and, weather permitting, we will continue searching until we have exhausted all reasonable possibility of finding these people.''
Deteriorating weather in the Haast area today limited the search, however more debris from the wrecked vehicle was found, Mr Canning said.
The van's chassis, found wrapped around a large boulder in the Haast River on Tuesday, has now been retrieved from the river.
Any future searches would be dictated by the weather, which was expected to improve by Sunday, Mr Canning said.
Relatives of the couple have told media they are holding out hope for their loved ones.
