An award-winning Russian alpinist is feared dead after falling from one of the world's tallest mountains in Pakistan, officials said Thursday, potentially the fourth fatality in the nation's 2023 summiting season.

Dmitry Golovchenko "suffered a likely lethal fall" from the 7,925-metre (26,000-foot) Gasherbrum IV -- the world's 17th tallest mountain -- sometime last week, the Alpine Club of Pakistan (ACP) said.

His partner Sergey Nilov was injured but made it back to the peak's basecamp on Pakistan's northeast border with China and was helicoptered out on Wednesday, the ACP said in a statement.

The pair had been "attempting a high-difficulty route", the statement said.

ACP secretary Karrar Haidri told AFP the alarm was raised by Golovchenko's wife, whom he was in contact with during the climb, and that he suspected the veteran mountaineer had fallen into a crevasse.

Authorities plan to launch a search effort on Friday, he added.

The Kremlin's embassy in Islamabad confirmed Russian mountaineers "encountered certain problems" on Gasherbrum IV and said it was "in direct contact with their families" in a statement to AFP.

Golovchenko and Nilov won a prestigious "Piolets d'Or" award -- described as the "Oscars of the mountains" -- in 2013 for their ascent of Pakistan's approximately 7,300-metre Muztagh Tower.

The pair won a second time in 2017 for a daring summit of India's Thalay Sagar via an unexplored buttress of ice and rock.

Golovchenko hailed from "a family of alpinists" and had been climbing with Nilov since 2002, his biography on the awards website said.

Pakistan is a hub for hardcore climbers, hosting five of the world's 14 mountains above 8,000 metres.

The world's second tallest mountain K2 is around 10 kilometres north of Gasherbrum IV in the Gilgit-Baltistan region, where the Karakoram mountain range is located.

The first casualty of Pakistan's summer climbing season was Polish national Pawel Tomasz Kopec, killed in July by suspected altitude sickness while descending 8,125-metre Nanga Parbat.

Later that month, a Pakistani porter died as hundreds ascended the K2 summit, including Norwegian climber Kristin Harila and her Nepali guide Tenjin "Lama" Sherpa, who the same day became the fastest people to summit the world's 14 highest mountains.

A Japanese man also reportedly fell to his death while climbing a never-scaled mountain in northern Pakistan in August.