The US will close 15 military bases across Europe, US Defence Secretary Chuck Hagel has confirmed.
The Pentagon says the move will save around $500m (£300m) a year, and comes as the US military seeks to shift its attention towards Asia.
But the US has named RAF Lakenheath to be the first permanent European base for the F-35 aircraft.
The US currently has more than 60,000 troops stationed in Europe, mostly in Germany, Italy and the UK.
The number will remain the same, as the US ramps up rotations within Europe for training programmes.
Many of the closures affect smaller bases that were remnants of the Cold War.
But US officials also have finalised plans to cut about 500 military personnel from the Lajes military base in the Azores islands, which drew opposition from Portugal.
The changes will mean a net reduction of about 2,000 US personnel in the UK over the next several years.
In the UK, the US Air Force will leave RAF Mildenhall in Suffolk and RAF Alconbury and RAF Molesworth in Cambridgeshire.
Mr Hagel said he understood it would mean job losses and thanked those who had supported the US Air Force.
"I know that this will result in a reduction of our local host nations workforces at some locations. I value the tremendous support they provided us for decades."
Other countries with closing bases include Germany, Belgium, the Netherlands and Italy.