The Colonel Commandant of the Parachute Regiment has penned a letter of support to Paratroopers deployed to Afghanistan to help with the UK's evacuation mission.
Troops from 16 Air Assault Brigade are currently deployed to Kabul, Afghanistan's capital, as the UK looks to get British nationals and eligible people out of the country.
Major General Andrew Harrison said in the letter only the personnel deployed to Kabul airport "will be able to understand the pressure they face".
"But they are bravely squaring up to an incredible challenge to save thousands of lives," he said.
"As our soldiers deployed onto the runway to face the chaos of a crumbling nation, they had no idea what the operation would bring.
"The threat of attack, from either the Taliban or from thousands of recently released prisoners, was everywhere.
"A second's loss of concentration could lead to separation and death and any moment rifle or rocket fire could bring disaster."
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"For days they have had no sleep," his letter continued.
"Most will have witnessed unimaginable levels of human desperation, viewed through the prism of fatigue and pressured decision making.
"Few, if any, will ever have seen anguish and fear on quite this scale and at such proximity.
"But, once again, our troops have proved ready for anything.
"This operation is far from over, and we wish them the very best of luck as they seek to forge order from chaos, to extract hope from despair."
Maj Gen Harrison added the campaign in Afghanistan had "not ended in the way any of us would have wished".
"Having spent years in Afghanistan, over multiple tours, I understand how painful this final chapter in the UK's involvement will be," he said.
"I feel for the Afghan population, but I also feel desperately sad for the families of our bereaved, the wounded, the veterans and all our families.
"But I want you to know that our reputation, carved out of the soil of Afghanistan by our soldiers, will endure forever."
He went on: "Our Afghanistan veterans have honourably served our nation.
"They have marched through Afghan dust to the sound of the guns and built on the extraordinary reputation this regiment holds.
"I will always be proud to be an Afghan veteran and will forever tell the amazing stories of our soldiers with pride.
"I will now salute fallen friends with a tear in my eye and my Herrick campaign medal worn proudly on my chest.
"As painful as it has been, I would not have wanted to be anywhere else," he added.
Cover image: Op Pitting is currently ongoing to evacuate British nationals and eligible Afghans from Afghanistan following the Taliban takeover (Picture: MOD).