A US-led coalition fighting to topple the Taliban has lost 1,500 soldiers, the US military said, with the Afghan government blaming the fall on the Taliban.
The casualty figure includes 2,735 US troops and 2,700 Afghan security forces.
It is the first fall since the end of the US-Afghan war in 2014, when the number of US troops in Afghanistan was cut to about 1,800.
In August, the Taliban’s military chief, Mullah Akhtar Mansour, said he was willing to hand over control of the country to a local government under US pressure.
The US and its allies have been conducting operations in Afghanistan since 2001, when US troops began withdrawing to the country after the collapse of the Soviet-Afghani empire.
The Taliban had been gaining ground in the country, particularly in eastern and southern Helmand province.
However, it has lost ground since the US pulled out, leading to the fall in US troop levels.
The announcement came as US President Donald Trump was meeting with Afghan President Ashraf Ghani, and Afghan and NATO officials said they would sign a security cooperation deal with the US next week.
The agreement would allow the two countries to share intelligence, train and equip each other’s forces, and coordinate their efforts in Afghanistan’s fight against the Taliban and other insurgent groups.
Afghan and US officials have been negotiating for more than a year on the deal.
The deal would also give Kabul more authority to oversee US troop withdrawal from the country.
The Pentagon said the number is a result of “significant increases in US personnel and equipment” that had not been anticipated by Kabul.
The Afghan government said the US troop count was “a result of a major reduction in the Taliban presence” and that it was “not a military victory”.
In Kabul, Afghan President Ghani said the United States and its coalition partners have failed to fulfil their obligations.
“I ask the US government to show them their responsibility for the people and the Afghan people.
They have not been honest to us, and I am the one who was asked to pay the price,” he said.
“Our country will not be pacified by US-backed forces.
The United States has not made us any progress in the fight against terrorism,” Ghani added.
The war against the insurgents has lasted more than 10 years.
The battle has killed at least 20,000 people, according to the United Nations, and left the country with the highest per capita homicide rate in the world.