We are in a "new reality" after voting to leave the EU and we "must accept it and make it work", David Cameron.
The prime minister made the comments at Farnborough Air Show as Boeing announced a plan to double its number of jobs in the UK.
The US plane maker intends to build a new £100 million facility for the P-8A Poseidon military aircraft at RAF Lossiemouth in Moray.
It will make the UK its European base for training, maintenance, repair and overhaul across its defence fixed-wing and rotary platforms.
The prime minister said: "I want the UK to continue to be at the forefront of the global aerospace industry, both civil and defence."
Three American families in the San Francisco Bay Area are suing Boeing over the deadly crash of Asiana Airlines Flight 214.
The San Jose Mercury News says the suits filed yesterday allege that the maker of the Boeing 777 provided inadequate training to pilots in South Korea.
However, it does not make clear whether Boeing trained the pilots of Flight 214, which crashed last month while landing at San Francisco International Airport, killing three Chinese teenagers.
A crash survivor is among those in the lawsuit.
The families also claim that Boeing should have added a "low airspeed" voice warning for pilots to the 777, following a similar crash of a Boeing 737 in Amsterdam four years ago.
Boeing said it is "supporting the actions by regulators" following a blaze on one of the company's 787 Dreamliner jets at Heathrow airport last week:
An Ethiopian Airlines' 787 Boeing Dreamliner flight has safely touched down in the Kenyan captial Nairobi approximately three months after air safety authorities grounded all the jets.
Two separate incidents with smouldering batteries in January saw all the Dreamliners grounded while engineers fixed the fault.
Boeing insists it has now fixed the problem and that all 787's will soon return to the skies.