Te Arawa woman Annie Doyle, who was attempting to become the first Maori woman to climb Mt Everest, is disappointed this year's expedition has been called off - due to warm weather.
Mrs Doyle, who is in the Himalayas, said on her internet blog that she and climbing partner Amanda Jones were "gutted".
"It is a tough decision - but it is the right decision," she said. "We will gather our thoughts, look inward for strength, knowing that it takes more courage and strength to say no. Not now, not this time."
Mrs Doyle said an expert Sherpa mountain guide called off the attempt, telling the expedition it was far too risky.
"Sherpas' lives, guides' lives and our lives are all at too great a risk with the conditions now being faced on Everest.
"Mother nature, the weather and conditions on the mountain have denied us the chance to try," she said.
A British expedition, Walking With the Wounded 2012, aiming to summit Mt Everest and put five wounded servicemen on top of the world, also said its climb was postponed.
Co-founder Edward Parker said the main issue was unseasonable dry and warm weather.
"The result of this is there isn't enough snow on the mountain side, leading to very loose rock, and hence, rock fall. Also, as the core temperature of the ice cliffs is higher than normal, there have been a far greater number of avalanches. Last week an avalanche narrowly missed a team climbing with our boys," he said.
Mrs Doyle, who lives in Sydney, was also striving to be the first Maori to summit the highest peaks of all seven continents. She has already climbed Mt Kosciusko in Australia, Mt Elbrus in Europe, Mt Aconcagua in South America, Mt McKinley in North America and Kilimanjaro in Africa. She will complete the seven when she climbs Mt Everest and Mt Vinson in Antarctica.
Mrs Doyle is of Ngati Pikiao descent, from Rotoiti.