Mount Everest
Light illuminates Mount Everest during a sunset in late 2015Reuters/Navesh Chitrakar

Britain's Leslie Binns gave up his quest to reach the top of Mount Everest to save the life of a fellow climber who was ascending ahead of him. An ex-serviceman man, Binns, was barely 450 metres away from reaching the summit when he turned around to save an Indian mountaineer who was sliding down the lines fixed for hiking.

If the 42-year-old had completed his trek, he would have been added to a list of successful mountaineers who have ascended the world's highest peak since Sir Edmund Hilary and Tenzing Norgay first conquered it in 1953. More than 4,000 climbers have reached the summit until February 2014.

Binns, from Yorkshire, served the British army for 13 years, and had lost an eye in a blast in Afghanistan. He was a victim of four blasts during his tenure in Afghanistan, Bosnia and Iraq.

He was only 12 hours from reaching the Everest peak when he returned to save the 32-year-old Sunita Hazra, when he heard her crying for help in the early hours of 21 May.

"All I could hear were the screams of terror as the person gained momentum. I braced myself to try and stop whoever it was, and managed to do so," Binns told the BBC. "I helped her upright and looked at her oxygen regulator. It was registering empty.

He decided to abandon his own mission to reach the summit after Hazra collapsed attempting to descend on her own, using his spare oxygen bottle to take her down.

He said the climbers found descending to be more dangerous and he took along with him another climber finding difficulty in descending the blue ice. However, due to exhaustion and terrible weather conditions he had to leave behind the other climber. When Binns resumed his descent the next day, he said he came across the body of the other climber they had to leave behind.

"I truly regret not being able to do anything more for him. But I had nothing left in me that night and I tried my level best to rescue him, but he could not be moved. No summit is worth a life. I'm immensely proud that I helped Sunita. I just wish I could have done more," Binns added.

Thanking Binns for saving her life, Hazra told a local television channel: "I owe my life to him [Binns]. I could return home to see my child. What else can I say?"

Her brother Kingshuk Chatterjee told the BBC how grateful he and his family are to Binns. "He's the reason why she is still alive now. He is a very brave man."

Meanwhile, Binns and his fiancé in the UK have been receiving congratulatory messages on social media from many mountaineers across the world.