Heavy bombers and fighter jets will be deployed to safeguard troops and civilian contractors.
The US and Nato have had a presence in Afghanistan for almost 20 years.
US President Joe Biden has set the withdrawal deadline for 11 September - the 20th anniversary of the 9/11 attacks that sparked the war.
But the withdrawal comes amid escalating violence, with Afghan security forces on high alert for reprisal attacks.
The Taliban have warned they are no longer bound by an agreement not to target international troops.
Under a deal signed last year between the militants and then-President Donald Trump, foreign forces were to have left by 1 May while the Taliban held off attacking international troops.
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