The search for a missing Italian climber and his British partner in Pakistan will resume Friday with the help of a team from Russia. Four Russian mountaineers who are currently at K2 base camp have volunteered to join the search for Daniele Nardi and Tom Ballard. Pakistani mountaineer Ali Sadpara and his colleagues Imtiaz Hussain and Dilawar Hussain will also join the team. The pair were last heard from on Sunday as they climbed Nanga Parbat in the western Himalayas, a peak known as “Killer Mountain”. The Russian team will be flown by helicopter from K2 base camp and left as close as possible to the missing climbers’ last known position following discussions with the Pakistan airforce, Nardi’s team reported on the climber’s Facebook page. Ballard is the son of British mountaineer Alison Hargreaves, the first woman to conquer Mount Everest solo and without bottled oxygen. She died descending K2, the world’s second highest peak, in 1995. Nardi’s team said on Facebook that the climbers’ tent had been “spotted from a helicopter, buried under snow. Traces of avalanches can be seen”. The search mission was delayed because rescue teams were forced to wait for permission to send up a helicopter after Pakistan closed its airspace on Wednesday in response to escalating tensions with India. The searchers have also called in Pakistani Muhammad Ali Sadpara, who climbed the peak two years ago, Nardi’s team said. The British Foreign Office said it was “assisting the family of a British man who has been reported missing in Pakistan”. Chris Bonington, mountaineer and a family friend of Ballard, told BBC Radio earlier Thursday that the pair were “attempting a very, very difficult route up Nanga Parbat, up the Mummery spur, which is the most direct route up”. “And they were trying to do it in winter, which is by far the toughest time. They’d certainly been having bad weather throughout, a lot of snowfall and it was also bitterly cold.” He said the temperature was believed to be minus 40, which may have drained the batteries on their phones. “There’s still hope that they are alive, and that they are ok, admittedly in very dangerous circumstances,” he said. Bonington said Ballard was “very much an extreme climber, taking after his mum”. “It is a very, very dangerous game. “I am very lucky to be alive. I’ve been climbing for what, 60 years, very nearly and… I was just unbelievably lucky to get away with it,” he added.