The Prime Minister has described her late friend and mountain guide as one of the most incredible people she has ever meet.
Gottlieb Braun-Elwert, who was 59, died from a suspected heart attack on the Two Thumbs range in South Canterbury on Thursday.
He was guiding Helen Clark and her party.
Miss Clark, who was visibly upset at a media conference in Tekapo on Friday, says the experience was harrowing.
"We tried to get help for him but in weather like that you just can't get a helicopter in," she says.
"The snow actually got worse and worse and we had very little visibility."
The Prime Minister and her party are all now en route to their homes.
A helicopter was dispatched to rescue the rest of the group on Friday morning from the Rex Simpson Hut.
A spokesperson for the Prime Minister earlier said she is shocked and distressed at the sudden death of a close friend.
Mr Braun-Elwert took trips with Miss Clark for the past 11 years. He was regarded as a pinnacle of the climbing community for nearly three decades.
He emigrated from Germany in 1978 where he worked as a nuclear physicist.
He made his base in Lake Tekapo where he began a mountain guiding company with his wife Anne, in 1981.
Mr Braun-Elwert climbed Mt Cook 26 times. In 1989, he climbed all of New Zealand's peaks over 3000m in one winter.