The intense search for two European climbers who went missing over a week ago in bad weather on the world's ninth-highest mountain in Pakistan was called off on Wednesday, after a Spanish-Pakistani search team lost hope of finding any trace of the pair.

Karrar Haidri, the secretary of the Alpine Club of Pakistan, told The Associated Press that it was not an easy but “a very painful decision” to take after the rescuers tried everything they could including flying out drones to find the two.

Earlier in the day, hopes had started fading for finding Italian Daniele Nardi and Briton Tom Ballard, missing for over a week on Nanga Parbat, known as “Killer Mountain” because of its dangerous conditions.

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Nardi, 42, from near Rome, had attempted the Nanga Parbat summit in winter several times in the past. Ballard, 30, also a skilled climber, in 2015 became the first person to solo climb all six major north faces of the Alps in one winter.

The two set out on Feb 22, making it to the fourth base camp the following day. The pair last made contact on Feb 24 from an elevation of some 6,300 metres (nearly 20,700 feet) on Nanga Parbat.

Haidri said the search team, headed by Spaniard Alex Txikon and experienced Pakistani mountaineer Ali Sadpara familiar with the peak, went on foot and used drones to search for the climbers.

After the search was called off, the rescuers were awaiting for a Pakistani military helicopter to take them back to the northern town of Skardu, where the search mission had set out from.

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Ballard's disappearance on the peak of 8,126 meters (26,660 feet) has hit Scotland particularly hard because he is the son of Alison Hargreaves, the first woman to scale Mount Everest alone. Ballard was born in England and grew up in the Scottish Highlands.

Hargreaves died at age 33 while descending the summit of K2, which is part of the Karakoram range on the border of Pakistan, India and China. The Karakoram range is among a complex of ranges including the Himalayas.

Before the search was called off, Italian Ambassador Stefano Pontecorvo tweeted about it and shared photos of the snow-covered mountain. Heavy snowfall over recent days had also raised fears that the climbers might have perished.

Bad weather last week twice forced the search teams to halt the operation but Pakistani military helicopters flew even after Pakistan shut its airspace over an escalation with neighboring India over the disputed Himalayan region of Kashmir.

Haidri had earlier said that “prayers are needed for the climbers”.