"When I met Sir James Dyson last month, he told me that our expertise in advanced manufacturing, global and regional connectivity, and the quality of our research scientists and engineers, all influenced Dyson's decision", said the prime minister.
The company plans to invest roughly £2 billion ($3.7 billion) on the project, most of which will be spent in Singapore.
In August of this year it announced the opening of an electric vehicle test center at one of its existing sites in the UK.
British technology company Dyson says it will build its electric auto in Singapore, with a new site set for completion in 2020 ahead of the first vehicle launch a year later.
Dyson CEO Jim Rowan also said that Singapore offers them access to big markets, highly skilled workforce and an extensive supply chain.
Dyson said the decision was based on the availability of engineering talent, regional supply chains and proximity to some key target markets, and had "nothing to do with Brexit".
Dyson already has roughly 1100 employees in Singapore, and hundreds of others in Malaysia, China and the Philippines.
The 71-year-old entrepreneur, who backed Brexit in the 2016 referendum, is pumping £2 billion (US$2.6 billion) into the launch of an electric vehicle, with a 400-strong British-based engineering team working in secret for the first two-and-a-half years on the project.
Dyson's move comes after a team of employees laboured in secret to fulfil their chief's longstanding ambitions to use technology to combat pollution.
Dyson purchased the American solid-state battery company Sakti3 three years ago, but so far that investment has been a write-off.
James Dyson told reporters previous year that his ambition to go it alone was driven by the auto industry's dismissal of an idea he had of applying his cyclonic technology that revolutionised vacuum cleaners to handle diesel emissions in vehicle exhaust systems in the 1990s.
Dyson plans to utilise what it's learned making vacuum cleaners with "switched reluctance" electric motors and apply that to cars.