US submarine-hunting aircraft will operate from RAF Lossiemouth following £62 million of investment by the United States.
It is understood America's investment will contribute towards the refurbishment of the runway, additional aircraft parking and hanger space and accommodation in order to meet their requirements.
The new facility at RAF Lossiemouth in Moray is expected to be completed in 2020, coinciding with the initial operation of the UK's new P-8A Poseidon maritime patrol aircraft.
It is part of a $717 billion investment in US defence spending, which also includes nearly $150 million to be spent at RAF Lakenheath.
The United States have previously operated from RAF Lossiemouth but it is reported that the improvements do not mean there will be a permanent US basing at the base.
Defence chiefs believe the RAF P8 fleet and the US submarine hunters will play a key role in keeping the UK and its allies safe.
A Ministry of Defence (MoD) spokeswoman said: "We are investing £3 billion in our nine-strong, new P-8A Poseidon fleet over the next decade.
"The contribution of 80 million dollars from the US to the home of our submarine-hunters at RAF Lossiemouth will support our partnership with our closest ally and will help us be more efficient by sharing improved facilities, and will see us patrol the seas together to have more eyes and ears on any aggressors."
In April, the MoD announced that RAF Lossiemouth was to be the future home of its new Poseidon fleet.
The aircraft will be used to protect the UK's submarine-deployed nuclear deterrent and its two new aircraft carriers, according to defence officials.